UK police on Saturday arrested a terror suspect who escaped from a London prison earlier this week, sparking a nationwide manhunt.

"Metropolitan Police officers have arrested Daniel Khalife. Officers apprehended him just before 11am (1000GMT) today in the Chiswick area, and he is currently in police custody," the force said in a tweet.

Prime Minister Rishi Sunak, currently in India at the G20 summit, told UK media he was "very pleased with the news". 

"My thanks to the police officers for their fantastic work over the past couple of days," he added.

The 21-year-old former soldier fled from Wandsworth prison in south London on Wednesday morning, probably by clinging to the bottom of a delivery van.

His disappearance triggered a major hunt with extra security checks introduced at ports and airports amid fears he may try to flee the country.

But following confirmed sightings in south west London, he was eventually apprehended in the Chiswick neighbourhood on Saturday.

He last appeared in court in London on January 28 and was remanded in custody over two incidents at the Royal Air Force base in Stafford, central England, near the army barracks where he lived.

Khalife is accused of "attempting to elicit information of a kind likely to be useful to a person committing or preparing an act of terrorism" in August 2021. 

He was also charged with a bomb hoax by placing a suspect device at the RAF base on January 2 this year.

His trial at Woolwich Crown Court -- attached to Belmarsh prison -- had been set to begin on November 13.

- Inside job? -

Khalife was reported to have been working in the prison kitchen when he absconded.

Justice Secretary Alex Chalk said earlier this week that strapping was found underneath the delivery van which appeared to indicate that Khalife may have held onto the underside of it in order to escape. 

Chalk also announced an independent investigation into the escape, which Sunak said Saturday would continue, and also ordered urgent reviews into the categorisation and placement of everyone held at Wandsworth prison and all those in custody for terror offences.

Wandsworth, which opened in 1851, is a Category B prison -- the second highest security level. Terror suspects and prisoners are routinely held in maximum security Category A facilities.

Rosena Allin-Khan, a lawmaker for the main opposition Labour party, told parliament that conditions for staff at Wandsworth prison were "unworkable and unsafe".

Chief Inspector of Prisons Charlie Taylor also said staff shortages were "the source of many problems".

John Podmore, a former governor at two prisons in London, told the BBC that the escape could have been an inside job, and that he should have been held at nearby Category A Belmarsh prison instead.

"It's much more suited to the levels of security that someone like this, charged but not convicted, needs. I can't understand why he wasn't at Belmarsh," he added.

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