Sir David Amess received an “upsetting threat” in the days leading up to his murder, according to colleagues.
Despite the alert, he chose to go ahead with his public appointments, including his surgery at Belfairs Methodist Church in Leigh-on-Sea, where he was stabbed multiple times on Friday lunchtime.
John Lamb, the former Mayor of Leigh-on-Sea and a close colleague of the Southend West MP, said: “I don’t know the nature of it, but it was rather upsetting and the police were alerted. It was in the past few days.”
Mr Lamb said Sir David wanted to hold surgeries in places like the church so he would be more accessible to constituents, rather than Tory Party offices in Southend.
He added: “Sir David used to hold them at the Conservative Association, but that made it hard for older people to see him, so around a year ago he started going out into the community.
“He didn’t want to hide away, he wanted to be visible and accessible. He told me: ‘I want them to be able to see me in their local area’.
“It’s a tragedy that someone has taken advantage of that to attack him like this.”
Sir David’s election agent Nigel Holdcroft said he understood that a threat had been made “in recent days”.
He told the newspaper: “Sadly, I don’t think there’s a member of Parliament who hasn’t [received threats].
“Unfortunately with social media, and the way that it is, that sort of threat is ever-present for them.”
Sir David, who had been an MP since 1983, was meeting constituents when he was stabbed to death.
Ali Harbi Ali, 25, was arrested at the scene in Essex on suspicion of Sir David’s murder.
He has been detained under section 41 of the Terrorism Act 2000 and is in custody at a London police station.
The Home Office would not comment on reports that the suspect has the same details as a man previously referred to Prevent, the Government’s anti-terror scheme.
Sir David’s killing comes after the Labour MP for Batley and Spen, Jo Cox, was murdered in 2016 on her way to a constituency surgery.
Scotland Yard - now leading the murder investigation declared a terrorism incident - said it was not prepared to discuss if Sir David received a previous threat.