A political aide has described the moment she saw a terror suspect with a look of “self-satisfaction” after stabbing to death her boss, the veteran Conservative MP Sir David Amess.

Julie Cushion, a long-term member of the Southend West politician’s constituency staff, recalled hearing a “piercing scream”, five minutes after Ali Harbi Ali was called to his appointment at a constituency surgery with Sir David.

Sir David, an MP since 1983, suffered more than 20 stab wounds during the frenzied attack at Belfairs Methodist Church shortly after midday on October 15 2021, and was pronounced dead at the scene.

Giving evidence from behind a screen at the Old Bailey, Ms Cushion, who made the first 999 call from the scene at 12.07pm, said the pair had engaged in “chit-chat” when Ali arrived, before being led into a back room to meet Sir David.

Her voice cracking with emotion, she said: “A piercing scream was the first thing I heard.

“And then a very loud crash which I assumed was furniture going over.

“I got up and walked through, I assumed something structurally had happened.

“Rebecca (Hayton, a fellow aide) came running towards me screaming that Sir David had been stabbed, he was on the floor.

“At that moment I picked up my phone to call for help.”

Asked how Ali looked, Ms Cushion said: “Self-satisfaction, I would describe it.”

The trial previously heard how Ali had allegedly spent years hatching his plot, researching a number of potential high-profile political targets including Michael Gove, Dominic Raab and Sir Keir Starmer, before settling on 69-year-old Tory backbencher Sir David.

Ms Cushion, who described Sir David as a “close friend”, said meetings had traditionally been held in his constituency office where there was a certain amount of security in place, but he decided to hold surgeries in other locations locally after coronavirus restrictions were lifted because he “wanted to be accessible to his constituents”.

Ms Hayton described to police hours after the incident how she saw Ali stand up and stab Sir David.

In her police video interview, played to jurors, the junior staff member wept as she said: “He (Ali) leans over and stabs him straight in the stomach.

“David screamed, and sort of panicked.

“I think he stabbed him again.

“I could see David screaming.”

She added: “I saw it (the knife) go in once and as I got up he (Ali) kept going.”

Ms Hayton said Ali had been “smiling” during the five-minute meeting with Sir David, adding: “He seemed relaxed and nice.”

She ran outside to raise the alarm and returned to the church with two members of the public, Yvonne Eaves and Darren King.

There, they saw Ali standing in the doorway between them and the prone victim, clutching the knife with a clenched fist. 

She said: “(Mr King) was trying to speak to the guy and he (Ali) was saying: ‘Don’t come any closer, don’t come any closer’.

“I heard him say ‘Don’t come anywhere near, I’m not going to hurt anybody else, call the police, call the police.’

“I basically told him (Mr King) to come out.

“Then he (Ali) was going: ‘Call the police, call the police’.”

Ali had managed to arrange an appointment with Sir David by duping his office into believing he was a healthcare worker moving to the area, who wished to discuss local matters.

Jurors have been shown CCTV footage of Ali’s near-two-and-a-half-hour journey from his home in north London to the appointment in Leigh-on-Sea in Essex, on trains and by foot along busy high streets and residential areas among unsuspecting members of the public.

He arrived at the church as planned but then sent a WhatsApp message to family and friends seeking to justify his actions, telling father-of-five Sir David he was “sorry” before plunging the carving knife into his victim, sending Ms Cushion and fellow aide Ms Hayton fleeing to safety.

The court heard Ali had a “warped” ideology and sought to exact “revenge” over Britain’s recent foreign policy, notably the bombing campaign on Syria in the mid 2010s, allegedly telling bystanders at the scene: “I want him dead. I want every Parliament minister (sic) who signed up for the bombing of Syria who agreed to the Iraqi war to die.”

Ali, from Kentish Town, has denied preparing terrorist acts and murder.

The trial continues.