A former Indian politician convicted of kidnapping has been shot dead live on TV along with his brother.

Atiq Ahmed, who was under police escort, was talking to reporters when a gun was pulled close to his head in Prayagraj, also known as Allahabad.

After the shots were fired on Saturday night, three men who had been posing as journalists quickly surrendered and were taken into custody. 

Ahmed's teenage son was shot dead by police days earlier.

Dozens of cases, including kidnapping, murder and extortion, were registered against Atiq Ahmed over the past two decades. A local court sentenced him and two others to life in jail in March this year in a kidnapping case.

Ahmed had previously claimed there was a threat to his own life from the police.

Video showed Ahmed and his brother, Ashraf, both in handcuffs, speaking to journalists on the way to a medical check-up at a hospital seconds before they were both shot. 

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In the footage, shared widely on social media and TV channels, Ahmed is asked whether he attended his son's funeral. 

His last words to camera are: "They did not take us, so we did not go."

The three suspected assailants had arrived at the site on motorcycles, the police said.

A policeman and a journalist were also injured at the scene.

Following Saturday night's incident, Chief Minister Yogi Adityanath ordered a judicial probe into the killings and banned large gatherings in the districts of Uttar Pradesh state to ensure peace.

Experts have raised questions on how a man could be killed in front of the media and the police. BBC Hindi correspondent Anant Zanane reported from Prayagraj that the city was in a lockdown-like situation. 

Who was Atiq Ahmed?

He had a long stint both in politics and with the criminal world. He was first accused in a murder case in 1979. In the next 10 years, he emerged as a person who had strong influence in the western part of Allahabad city. 

He won his first election as an independent candidate and became a state lawmaker in 1989. He went on to win the seat for two consecutive terms and his fourth win came as a lawmaker from the regional Samajwadi party (SP). 

In 2004, he won a seat in the federal election as an SP candidate and became an MP. Meanwhile, cases continued to be filed against him in Allahabad and other parts of the state.

Ahmed contested a few more elections in the next decade but lost all of them. In 2019, India's top court ordered that he should be moved to a jail in Gujarat state after it emerged that he planned attacks on a businessman from a prison in Uttar Pradesh where he was being held awaiting trial in another case.

He was brought back to Prayagraj in March from Gujarat to appear in a local court as it announced his sentencing in a kidnapping case.

Ahmed was also brought to the city to be questioned in other cases. His brother Ashraf, who was in a jail in Bareilly district, was also brought to the city to be questioned.

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They were both being questioned in the February murder of Umesh Pal, a key witness in the 2005 murder of Raju Pal, a lawmaker belonging to the regional Bahujan Samaj Party (BSP). 

Raju Pal had defeated Ashraf in the 2004 assembly elections in Atiq Ahmed's political stronghold.

Umesh Pal was killed in February this year when several people fired at him. 

Atiq Ahmed's teenage son Asad and few others were named as the main suspects in the Umesh Pal murder case. Asad and another man were killed by police earlier this week in what was described as a shootout. 

'Crime has reached its peak in UP'

Last month India's Supreme Court declined to hear Ahmed's petition in which he alleged there was a threat to his life from the police.

Uttar Pradesh is governed by the Hindu-nationalist BJP, and opposition parties criticised the killings as a security lapse.

"Crime has reached its peak in UP and the morale of the criminals is high," Akhilesh Yadav, chief the opposition Samajwadi Party, tweeted in Hindi.

"When someone can be killed in firing openly amidst the security cordon of the police, then what about the safety of the general public. Due to this, an atmosphere of fear is being created among the public, it seems that some people are deliberately creating such an atmosphere," he added.

More than 180 people facing various charges have been killed by police in the state in the past six years.

Rights activists accuse the police of carrying out extra-judicial killings, which the state's government denies.

The police usually calls them "encounters" - many say these are really staged confrontations which almost invariably end with dead criminals and unscathed police.

Encounters carried out by police are - at least in part - a response to India's grindingly slow and dysfunctional criminal justice system.