Nigerians are outraged by the unveiling of a new police unit to replace a notorious agency that was disbanded following public outcry over its alleged human rights abuses.

The head of the police Mohammed Adamu announced that Swat would carry out the duties which were done by the Special Anti Robbery Squad (Sars).

But many are using the hashtag #EndSwat on Twitter to oppose the new unit.

They see the changes as not enough to reform the police.

Thousands of Nigerians have been protesting against the frequent cases of illegal detentions, assaults and shootings by Sars officers.

The mostly peaceful demonstrations have however been disrupted by police. Amnesty International said on Tuesday that 10 people were killed in the protests but other reports give a lower figure.

Some of Nigeria's biggest music stars, including Davido and Falz, have thrown their weight behind the demonstrators, who have been galvanising support on Twitter under the #EndSARS hashtag.

On Tuesday, they marched in the oil hub of Port Harcourt in defiance of a ban on demonstrations imposed by the state governor.

Protests were also held in the commercial hub, Lagos, the country's capital, Abuja, and four other cities.

What did the police chief say?

In a statement on Tuesday, Mr Adamu said all Sars staff will undergo a psychological and medical examination before further training and redeployment.

The new Special Weapons and Tactics (Swat) team will fill the gaps left from the dissolution of Sars, he said.

The police chief also ordered the release of all detained protesters after a meeting with the National Human Rights Commission.

He did not say how many of them were in detention.

Mr Adamu added that Nigerians had the right to protest peacefully and ordered officers to stop using force against them. He acknowledged that the protesters' concerns were genuine and said they would be addressed by the government.

The meeting also agreed that an independent panel would be set up to investigate allegations of abuse against Sars, and other police units.

On Monday, Mr Buhari promised that the disbandment of Sars was only the first step towards "extensive" reforms within the police force.

What are people saying?

On Twitter, where the protests have been organised, many people are using the hashtag #EndSwat to remind others about their goal of reforming the police.

https://twitter.com/VOwugah/status/1316284303626641409?ref_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1316284303626641409%7Ctwgr%5Eshare_0&ref_url=https%3A%2F%2Fwww.bbc.com%2Fnews%2Fworld-africa-54531449

https://twitter.com/is_salsu/status/1316282413719355392?ref_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1316282413719355392%7Ctwgr%5Eshare_3&ref_url=https%3A%2F%2Fwww.bbc.com%2Fnews%2Fworld-africa-54531449

Others suspect that the government is trying to sow division amongst the protesters and are urging solidarity.

https://twitter.com/tokstarr/status/1316284588604391425?ref_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1316284588604391425%7Ctwgr%5Eshare_3&ref_url=https%3A%2F%2Fwww.bbc.com%2Fnews%2Fworld-africa-54531449

How did Sars operate?

The latest round of protests were prompted by footage of officers pulling two men out of a hotel in Lagos into the street and shooting one of them.

The footage, leaked to the media, provoked outrage and led many to share stories of brutality attributed to the unit.

Earlier this year Amnesty said it had documented at least 82 cases of torture, ill treatment and extra-judicial execution between January 2017 and May this year.

The victims were mainly men aged between 18 and 35 from poor backgrounds and vulnerable groups. Many of those tortured were beaten with sticks and machetes and denied medical attention, the group said.

The "systemic use of torture... points to an absolute disregard for international human rights laws and standards", Amnesty said.

Why didn't reform work?

The #EndSARS hashtag was first thought to have been used in 2018, but it emerged again a fortnight ago.

There have been earlier attempts to reform the notorious squad. In 2018 Vice-President Yemi Osinbajo ordered that its management and activities be overhauled.

Then last year, a specially formed Presidential Panel on the Reform of the Special Anti-Robbery Squad recommended reforms along with the dismissal and prosecution of named officers accused of abusing Nigerians.

At the time, President Buhari gave the head of police three months to work out how to implement the recommendations, but critics say little changed.

Previously police chiefs ordered a reform of Sars in 2017, in the aftermath of a viral video of a man allegedly killed by police, and also in 2010 when instructions were given to disband satellite offices.

Yet the unit has continued to exist despite these announcements.