"God Forbid."

Shortly after sunrise on the morning of Saturday 7 October, a message pings on 200 phones of the Be'eri mothers' WhatsApp group.

Minutes later another message lands: "We have a terrorist on the stairs. Call someone."

WARNING: Some readers may find details in this article distressing.

Hamas gunmen had just begun a day-long rampage through this kibbutz in southern Israel, and over the next 20 hours the women channelled their horror, disbelief and reassurances through the chat - as militants roamed the neighbourhood shooting residents dead and setting fire to homes.

Hiding in their safe rooms these women - some huddled with their families - described the shouts and explosions they heard outside, told each other where gunmen were, shared tips on coping with smoke that filled their rooms, and repeatedly called for help. In some cases, that help never came.

As the hours ticked by, they asked questions. Where was the army? Why was help taking so long? Can somebody please look for my mother? How do I lock my safe room? Should we open the door to a man claiming to be a soldier?

At some point, somebody changed the name of the group to "Be'eri Mothers Emergency".

This group chat was shared with the BBC by a woman put forward by the community to speak to the media in the wake of the attacks. She is one of the mothers on the chat and shared the details with us so we could see how the terror of the day unfolded - and what a lifeline these women were in the most desperate and sometimes final hours of their lives.

We could not seek the permission of all 200 members, but three of them agreed to tell us their stories in detail, and we have anonymised all other exchanges, being careful to ensure nobody can be identified to protect their privacy.

Some members are unaccounted for, presumed dead or missing. Survivors estimate that about 100 people were killed and many were taken away as hostages.

Minute-by-minute, this chat reveals in detail not seen before how Hamas stalked, murdered and burned people in their own homes, coming back again and again. It is an insight into what it felt like across southern Israel as Hamas gunmen crashed across the border and tore through dozens of communities.

It shows how residents survived and supported one another - but it also documents, hour by hour, their growing desperation, as it became clear they would not be rescued by the Israeli state anytime soon.

Dafna Gerster, 39, was visiting from Germany and had spent Friday night with family in the kibbutz she grew up in. They had gathered at her father's house, playing the board game Camel Up into the night - and then she and her husband slept at her brother's apartment nearby knowing the next day was Saturday, the Jewish day of rest, when the families could be together again.

The community is next to the Gaza border and is used to missiles - but when Dafna awoke to the scream of rockets at 06:30, she knew immediately that something was different.

"Usually you have an alarm and a boom of the iron dome [Israel's missile defence system]. This time, there was no alarm, and it was so loud. It's a sound we could not identify.

"I went to my brother's room and asked him 'what is this?'"

Like others in the kibbutz they rushed to the safe room or mamad - a room made of reinforced concrete with airtight steel doors and windows designed to withstand rocket attacks.

But it soon became clear that rockets were not the only threat. News spread on the WhatsApp group that someone had been shot - and that there were armed men in the streets.

CCTV footage verified by the BBC shows a small group of Hamas militants arriving at the gate of the kibbutz before 06:00. A car arrives, the gate opens, and the militants run inside after shooting dead the occupants of the vehicle. Video from a few minutes later shows the same two Hamas militants walking through a square, guns by their side.

Fast forward to 07:10, as the first messages on the WhatsApp group are being shared. Video shows three motorbikes, each carrying two heavily armed Hamas militants, leaving the area by the same gate.

Other footage, which is too graphic to include here, shows militants in the kibbutz at 09:05 - three hours after first entering. It shows the same car that was shot at in the first clip with at least one body dragged out, lying in the road.

Across the kibbutz, as the community collectively barricaded themselves into their own mamads, a rising sense of dread on the chat preceded a horrible realisation: many people were struggling to lock their safe room doors.

"How do you do an emergency lock? And how do we know that it is really locked?" one asked.

"Can you lock the safe room?" asked another.

"To missiles yes, not to terrorists."

Pictures shared on the WhatsApp group offered tutorials on locking the doors. Those who couldn't feared Hamas would just walk in.

At the house of Michal Pinyan, 44, her husband had run out of the safe room to lock the front of the house. The family heard shouting in Arabic outside, followed by gunshots.

After rushing back to the safe room, Michal's husband built a locking device with ropes and a baseball bat, which he gripped for the almost 19 hours they spent in the room.

In the terrified silence of these safe rooms, where people would not dare scream, they typed frantically. Michal watched the messages stream in.

They could not hear what was going on outside except via muffled sounds through the thick walls. But from what little they could make out, they collectively tried to understand what was going on.

They shared messages of "frantic knocking" on their doors as gunmen went house to house.

"Not knocking - it's gunfire," one said.

During the first hour of the attack, people would tell the group they could hear shooting in their neighbourhood, or outside a particular house. The replies inevitably poured in: "So do we."

"We understood it wasn't just one terrorist, it was a massive attack," Michal says. "In each neighbourhood of the kibbutz we heard 'they're here, they're here' so they were in each neighbourhood at the same time."

As the scale of the assault became clear, frustrated, fearful posts flooded the chat asking when the army was arriving - and why it wasn't there already.

"You can hear shooting close by. Hoping it's the first response squad firing," one woman wrote, referring to a small unit in the kibbutz that responds to intruder alerts before handing over to the military.

Dafna's brother, Eitan Hadad, was part of that unit and rushed to help, leaving the couple in the safe room.

It would be the last time she saw him.

"He went out and we stayed in the safe room and it was just horror," she says.

"You didn't know what was going on, you just hear shooting all the time, bombs, a fight. And it doesn't stop for a minute."

The response unit of roughly 10 people was clearly no match for the Hamas militants.

On WhatsApp, people reported more and more gunshots - and men speaking Arabic outside. The desperate pleas for help became more frequent.

"I'm home alone and I'm really scared," one resident wrote.

Elsewhere in the kibbutz, Shir Gutentag was trying to quietly comfort her eight-year-old and five-year-old daughters, while following the WhatsApp chat in disbelief.

"At first when I realised we have terrorists in the kibbutz I shook. I was in shock. But very quickly I thought to myself 'you have to stay calm', because they're looking at me, my children, and they see my reactions and they're starting to panic," she says.

"So I told them it's OK. It's going to be OK."

Hours had passed since the attack started, and the crisis was only worsening. Hamas were breaking into people's homes and threatening safe rooms as members of the chat begged for help.

Michal was reading these pleas for help while also messaging her own family in a separate WhatsApp group. She shared the contents of this group with the BBC, giving a terrifying insight into one family's despair as they detailed the Hamas attack in real-time.

At around 09:30, Michal's mum wrote on the family chat that she could hear voices in Arabic outside their house. Within 15 minutes another message confirmed that Michal's dad had been hurt.

Michal, who had been trying to stay silent in her safe room until this point, simply could not keep quiet anymore and rang her mother. Her mum picked up the phone and whispered.

"'They're here, they shot Dad, he's not OK.'

"And then she hung up,'" Michal says.

Her mother continued writing on the family chat: "Help. Help."

Hamas gunmen had used a weapon to break through the safe room door and had shot Michal's father as he tried to fight back. They then threw grenades.

Her mum wrote a final plea for help at 10:15. After that, messages from her children went unanswered. She had been killed too.

As her parents were being attacked, Michal was desperately messaging in the mothers' chat, calling for someone to help them. She would continue posting messages about them throughout the day hoping that, somehow, they had survived.

She was not the only one. Others were continuously begging for someone, anyone, to check on their parents, friends, cousins. But nobody could: everyone was in the same situation, barricaded in their own mamads.

Guns and grenades were Hamas' weapons, but they also set homes on fire.

"The entire house is smoke," one resident wrote. "What should I do… tell me what to do."

"We have a fire inside the safe room", "The entire window of the safe room is black", other messages read.

On the row of houses closest to Gaza, the home of Dafna's disabled dad, Meir Hadad, was being burned down.

In their own family chat, Meir's Filipina carer, 52-year-old Bhing Sol, pleaded with his children to find help.

"They're here," she wrote, referring to Hamas, in a message at 09:44.

"It was full of terrorists," Bhing later said, saying they looted the home before setting it on fire.

"The safe room was full of smoke. I keep on asking everyone to help us because maybe we'll be burnt alive. But nobody could help us because everyone is terrified."

In the mothers' group, others also asked for help to be sent to Meir.

With little anybody could do to answer all these pleas they offered each other practical suggestions - small, homespun survival tips that sustained them, and perhaps even saved lives, in their most powerless moment.

This was the spirit of the WhatsApp group - not just today, but for the years it had existed. It was a place for mothers to vent, to give advice, to support one another.

"Entire house is full of smoke what should I do?" someone asked. "Try to put a wet cloth on your face. Or urine," another resident responded.

In another exchange, a resident wrote: "I can't breathe in the house I think there's a fire here help urgently".

"Stay in the safe room don't go out put a piece of cloth on your nose," a neighbour replied.

While 44-year-old Golan Abidbol's wife and children took shelter in the family's safe room, he stood with a gun in his kitchen, watching Hamas militants throw a molotov cocktail at another building. As he watched, he saw a family jump from the second-floor window and hurry to a neighbour's safe room.

"I was pumped up with adrenaline. If someone came to my house I would give them the fight of my life," he says.

"I sent pictures to the neighbour downstairs because his house started to burn. I told him: 'Now. I don't see anyone. It's a good time.' So he moved to another neighbour's shelter."

Golan says this is the "essence of the kibbutz".

"We are one big family. If we need to open our door when there are terrorists outside and let the neighbours get in so they can survive, we will do it. No one even hesitated," he says.

At around midday, two or three men tried to enter Golan's house. He pulled the trigger. "They returned a burst of fire on the house and then they left. I don't know why they decided to do it but they decided to leave and not engage me anymore," he says.

At the same time, harrowing messages in the group continued to show that Hamas were breaking into houses and trying to breach safe rooms. "Firing at our safe room's door," one message read. "Helppp. Anyone."

Meanwhile, at the burning house of Bhing Sol and Meir Hadad, gunmen had begun shooting at the safe room as it filled with smoke.

"I took a risk - I opened the window of the safe room, thinking even a little bit of space and the air will come," Bhing says.

"They kept bombing, with a grenade or something, inside our house. I knew it was burning because the door was so hot it was like fire. But I kept holding the door with a blanket because I didn't know if they could open the door," she says.

Later in the day, in what Bhing describes as a miracle, a crack formed in the ceiling of the room and water started dripping through onto Meir's head. She grabbed his cheeks in joy after the first drops fell and rubbed her hands over her face.

As they waited, the pair could hear hostages being taken past them towards Gaza.

"I heard so many people that they brought outside, then I heard shouting, and then Hamas was laughing and rejoicing that they got someone," Bhing says.

The first reference on the mothers' chat to someone being kidnapped was at 12:09.

The BBC has verified footage taken on the day that shows Hamas militants leading five hostages, including an elderly woman, down the road in Be'eri kibbutz - we do not know what time this footage was taken. Israel says that, in total 150 people have been kidnapped and taken to Gaza and it is unclear how many were taken from Be'eri kibbutz..

As some people were led away by Hamas, others wondered when the army would arrive.

Shir Gutentag was reading the messages, while trying to comfort her daughters by continually placing a hand on each of them.

"I heard voice messages of terrible things," she says. "There was a woman saying her baby daughter was dead. She was crying for help. Another one saw her mother getting killed, and she's waiting in the safe room for many hours whispering for help saying 'save me, I don't want to die.'"

Other WhatsApp messages in the group tell of horrific injuries - including a family member bleeding from a massive wound.

There are many messages on this chat, including some describing injuries, but we have not been able to ascertain the fate of everyone who posted.

As they sat waiting in the safe rooms for Israeli soldiers to arrive, the residents continued to support one another.

Shir made quiet calls to neighbours who had posted messages showing they were in distress, saying "breathe in with me".

"I posted mainly encouraging things - I'm sure the army's there, I'm sure they're coming. Be patient. Breathe," she says.

Others in the group did the same.

In one exchange, someone asked: "Is there something someone can say to calm us down?" Within seconds a neighbour responded: "I'll tell you," before describing how the army would be able to handle it.

At around 15:00, Shir got a call from neighbours asking to come into her home because theirs was filling with smoke.

She rushed over to her front door, and began dismantling a stack of furniture she had put against it to stop anyone entering and let the family of four through, ushering them to the safe room before reassembling the barricade. A few minutes later, another woman got in touch to ask to enter and Shir began the process again.

As her family waited for a rescue they weren't sure would happen, Michal said she put her hands on her three children and "gave them little kisses, but quietly".

A message on the WhatsApp group offered advice about how to keep children calm. The message said that fear is normal, and to calm children with a hug.

In the afternoon, updates shared in the group suggested that IDF soldiers had arrived, and were beginning to make headway. "The soldiers are now fighting... Two other forces are on their way," one message just after 15:30 said.

People continued to post their addresses in the hope that someone would come to save them, adding brief information, such as "terrorists hiding".

But confusion continued to dominate and nobody seemed to know how many soldiers had arrived, or if they were an organised group who could begin to control the situation.

People reported hearing shouts of "IDF, IDF!" outside, but did not know whether this could be trusted. It could be Hamas in disguise, trying to tempt residents to open up.

Golan had continued standing with his gun in his kitchen and he said he could see miltants with RPGs shouting "IDF, IDF."

"I text my neighbours saying I didn't think it was IDF, they had an accent and they didn't dress appropriately - they wore the uniforms, but they didn't wear them right."

This message was also being passed around in the group.

"They're also disguised as soldiers, do not answer anyone outside," one said.

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As evening approached, messages became more hopeful. The sounds people were hearing from the safe rooms were shifting. Many were hearing more Hebrew voices.

They had been waiting for almost an entire day for help. In one of the first messages on the chat one member says people should not worry and that they didn't need the army - it would be all over soon. But a few minutes later, people were begging for soldiers to come.

Now that help had finally arrived, residents tried to coordinate with soldiers, calling out locations for IDF troops to be sent to fight.

Shortly before 18:00, a message was circulated saying the most senior forces in the army were handling the incident. "Until now you were brave and amazing, keep staying in the safe rooms and the incident will end. Everyone is aware of the situation and information is coming through all the time."

It was around this time that Bhing and Meir were rescued from their safe room. The house around them - where the family were playing board games the night before - was now ashes. Somehow, they had survived, trapped inside a tiny room as all their belongings burned.

Bhing turned as soldiers escorted them away, and took a photo on her phone of the remains.

Back in the group, a message was sent at 18:08 saying: "They're beginning a process of evacuation." This was followed by the first messages from people saying they had been saved.

But the process was slow. Many continued to plead for help long into the evening. "Lots of bullets here too. It doesn't stop. Please they're here," one message just after 19:00 said.

The military arrived at Dafna's brother's apartment at 20:00, telling Dafna and her husband they would be rescued within an hour.

Members of the mothers' group began sharing code words the soldiers should say so residents could trust it was really them. People continued to worry that it was really Hamas trying to get into their homes.

Meanwhile, the sounds of gun battles continued. They were being told it was over but as they had spent a day seeing nothing but hearing everything, they felt they could not distinguish anything or trust anybody.

"They're not saying the code help us," one resident wrote.

When the military came to Michal's home, she initially refused to open the door. One of the people from the kibbutz's emergency call-up unit called Michal's husband to assure him it really was the IDF.

"They told him they're going to come back and they're going to shout. And he said tell them to shout our name and we will open," Michal says.

The soldiers formed a circle around the family and their pet dog, as they escorted them from the kibbutz.

"They told us 'we're going to go quiet and at some point you've got to cover your kids' eyes because there are a lot of bodies outside'.

"So we walked, with the dog and he was really, really quiet. It took us I think 15 minutes to get outside of the kibbutz where they gathered all the people. The soldiers came to each family like this, so it took a lot of time."

She covered her children's eyes, but Michal kept hers open.

"I wanted to look. I saw bodies. My husband said he saw bodies of people from the kibbutz, but I saw bodies of terrorists," she says.

Others couldn't bear seeing the remains of their community. "I was looking down," says Shir. "I think this saved my soul."

As they waited to be taken away, a gunman opened fire nearby. It wasn't completely over.

The residents were brought on army trucks to a nearby town, before being moved on to a hotel at the Dead Sea.

Dafna, who had first seen the military at 20:00, wasn't rescued until after 01:00. She had spent the past 19 hours in such a heightened state of stress and horror that she had not worried too much about her brother. Later, she learned that he had died.

He was not the only one.

One woman who has been calling for help the entire day after Hamas broke into her house sent a flurry of posts around 17:00. They began with a haunting, whispered voice note: "I need help."

Others told her to hang in there.

At 18:00, she posted again.

"We must be evacuated," she said.

These were the last messages from her that the BBC saw on the WhatsApp chat. Her friends say she is either dead or kidnapped.

They look back to life before that first message - "God forbid" - to a time where their community was what they call a paradise. They describe a beautiful landscape, a community of mothers and friends that relied on each other and looked out for their neighbours.

Surviving residents say they are drawing strength from their broken community - but cannot forget those who have been lost.

"They are our friends, they are our family, they are everything to us," Golan says.

"We know them. They have been part of our lives since we were born and we want them back."

The residents had built a community in kibbutz Be'eri over decades. To them, it felt unbreakable. Now, many do not know where to go and what to do.

"I don't know if we'll even have a home to go to after this," Dafna says.

"We were living in an illusion that we were safe."

Translation by Shaina Oppenheimer, Jonathan Beck, Liora Schurr, Jonathan Shamir, and others

Design and visualisation by Tural Ahmedzade and Joy Roxas

Verification by BBC Verify team

Edited by: Samuel Horti