Terror trial shown images of arrest by armed police outside Parliament

The moment armed police swooped to arrest an alleged knife-wielding terrorist outside Parliament has been played in court.

Khalid Ali, 28, was detained in Whitehall on April 27 last year, four weeks after Khalid Masood brought carnage to Westminster.

Jurors at the Old Bailey were shown CCTV of Ali's arrest while crowds of people milled around Parliament Square.

As officers moved in they shouted out to Ali: "Armed police. Armed police."

The trained plumber put his hands in the air by his head and lowered himself to his knees then onto the ground.

Asked if he had anything on him that could harm a person, Ali said: "You'll see."

Two knives were retrieved from his jacket pockets and a third from the waistband of his tracksuit bottoms.

Ali allegedly set out that day armed with three knives to bring a "message" to British decision-makers.

The court has heard he planned an attack in the UK after spending five years with the Taliban in Afghanistan making bombs.

He carried out "hostile reconnaissance" around Downing Street, New Scotland Yard, the Ministry of Defence, the MI6 building and the Cenotaph on March 18 and April 22 last year, the court heard.

Jurors were shown CCTV footage tracking Ali's movements around Westminster in the days before his arrest.

The prosecution alleges Ali was targeting MPs, police and members of the armed forces.

Early on April 27, his mother raised the alarm when she found knives in his bedroom at the family home in Edmonton, north London.

But he re-armed himself with more knives from Wilko before taking the Tube to Westminster, the court heard.

His mobile phone was later recovered from where he had dropped it in the River Thames in Westminster, the court heard.

Ali denies two charges of possessing explosives with intent abroad in 2012 and one charge of preparing terrorist acts in Britain.