The terrorist who stabbed two people in Streatham boasted to prison pals about his plans to commit an atrocity bigger than the London Bridge attack, it is claimed.
Police shot dead Sudesh Amman after he stabbed two passers-by in Streatham, London, on Monday, just days after being released from jail.
A security source has now shed light on how the extremist bragged about his murderous intentions while behind bars.
He reportedly told fellow lags in December of how he wanted to carry out an attack 'worse than London bridge'.
During his time inside, he also revealed his plans to join ISIS after his release so 'everyone will come under the black flag' of the terror group, it is claimed.
Mail Online reports that Amman told other inmates at HMP Belmarsh about his desire to murder an MP and his regret at not having killed a British soldier.
Justice officials were unable to prevent the terrorist's release, despite being aware of his plans to launch an attack, a source said.
They added: "Under the law there was simply no way to keep him locked up.
"That is precisely why he was under 24-hour armed surveillance. No one was under any illusion about how dangerous he was.
"In terms of monitoring, the state was doing the maximum it can, but it wasn't enough to stop him."
Ministers are now working to prevent six other terror convicts from being let out of jail over the net few weeks.
Amman was blasted by police on Sunday who had tailed him following his recent release from jail.
The extremist had swiped a knife from a shop before wildly stabbing two people. As shots rang out, flying glass injured a third innocent bystander.
A woman attacked by Streatham terrorist Sudesh Amman has revealed she escaped harm because he tried to stab her with a knife still in its plastic packaging.