The suspected killer of Sir David Amess attended an official deradicalisation course, the Daily Mail can reveal today.
Ali Harbi Ali, 25, was referred to the flagship anti-extremism scheme, Prevent, which aims to stop individuals becoming terrorists.
The revelation raises urgent questions about the mentoring scheme and whether an opportunity was missed to avert the MP's horrific murder.
Sir David's family said their hearts had been 'shattered' by his 'cruel and violent death' at a constituency surgery in Essex.
They said they could not understand why the 'patriot and a man of peace' was targeted by a knifeman he had never met.
The 69-year-old father of five was ambushed at his Friday meeting with the public and stabbed 17 times in a frenzied attack.
In a heartbreaking statement his family called for people to 'set aside hatred', adding: 'Nobody should die in that way. Nobody.
'Whatever one's race, religious or political beliefs, be tolerant and try to understand. We are absolutely broken, but we will survive and carry on for the sake of a wonderful and inspiring man.'
Left to right: Katie, wife Julia, Flo, Sir David Amess, Sarah and Alex
Forensic officers at the scene near the Belfairs Methodist Church in Eastwood Road North, Leigh-on-Sea, Essex
Prime Minister Boris Johnson and Labour leader Sir Keir Starmer join Home Secretary Priti Patel and the Speaker of the House of Commons Sir Lindsay Hoyle as they pay their respects to Sir David
Detectives were last night still quizzing Ali who was arrested on suspicion of Sir David's murder at Belfairs Methodist Church in Leigh-on-Sea on Friday.
The British-born Muslim, who is of Somalian descent, had been referred to the Prevent programme over radicalisation fears by a concerned member of the community.
It is understood that the referral was not made by a member of the police or the security services.
It is not known whether it was a friend or relative, or someone from healthcare, education, social services or a religious group.
It resulted in Ali taking part in a course, which is believed to have been a 'Channel' mentoring scheme. Despite this intervention, which is thought to have taken place several years ago, MI5 was apparently not alerted and Ali was not investigated as a potential terror threat by police.
Priti Patel said a review of Prevent would examine whether it was 'fit for purpose'.
'It's right that we review what works, what doesn't work, what needs bolstering if there are any gaps, all of that, because Prevent isn't just about policing,' the Home Secretary said. 'Prevent is about how multi-agency partners come together.'
Police officers erect a tent outside a house in north London, thought to be in relation to the death of Sir David
People look at flowers left by the police cordon nearby the Belfairs Methodist Church
Yesterday critics questioned whether experts missed opportunities to stop a suspect described by investigators as a 'lone wolf' extremist.
Sam Armstrong of the Henry Jackson Society think-tank said: 'Questions must be asked about this case. Counter-extremism professionals seem to have lost sight of their duty which is to prevent terrorism.
'There has been an under-referral of Islamist cases and an over-referral of extreme Right-wing cases and we are now seeing the deadly consequences. The Prevent review has been derailed by Left-wing groups trying to litigate every aspect of its work and yet a cold hard look at the number of cases in which Prevent has fallen short shows this is only the latest in a long line.'
The Home Office scheme, which has an annual budget of around £40million, has been under scrutiny for years after a series of terrorists slipped through its net, including Reading attacker Khairi Saadallah.
The Government first promised scrutiny of Prevent in 2019, the year after parliament's intelligence and security committee highlighted a series of shortcomings.
But the independent review did not start formally until earlier this year and has still not reported back to Miss Patel.
Former justice secretary Robert Buckland called for a shake-up of Prevent to ensure a more 'joined-up' approach. He said more co-operation between schools, the NHS and other public agencies was required to ensure security forces could intervene early and prevent attacks.
'I very much hope that when it comes to community supervision and community involvement with people like this particular individual, that it is much more joined-up between health services, education, whatever it might be, who have had some involvement with that individual in the past,' he told Times Radio.
'And that element of being joined-up is what we really need to work on urgently.'
He added: 'There may be records or information from schools or colleges or from the health service which can tell us much more about individuals and their activities. We need to join this up much more effectively because what we're talking about here is community prevention.
'We've got to make sure that every arm of the state is absolutely working together in order to understand as much as possible about these individuals, and then to intervene if we judge the risk to be so significant that an intervention could prevent the sort of appalling incident that we saw not just last week but also in the Jo Cox case and other examples.'
Mrs Cox, the Labour MP for Batley and Spen, was murdered by a far-Right fanatic in the street in 2016 as she was about to carry out a constituency surgery.