The London Bridge attacker has been named as convicted terrorist Usman Khan, police said.
Metropolitan Police Assistant Commissioner Neil Basu said 28-year-old Khan had been living in the Staffordshire area and officers were searching an address in the county.
He added police were “not actively seeking anyone else” over the attack, which left a man and a woman dead.
“This individual was known to authorities, having been convicted in 2012 for terrorism offences. He was released from prison in December 2018 on licence and clearly a key line of enquiry now is to establish how he came to carry out this attack.”
Khan was wearing a fake suicide vest when he was killed on London Bridge on Friday afternoon in full view of horrified onlookers.
Three people – a man and two women – were also injured in the rampage and are being treated in hospital, Mr Basu said.
The Stoke-on-Trent-based radical, along with two co-conspirators, originally received an indeterminate sentence for public protection but this was quashed at the Court of Appeal in April 2013 and he was given a determinate 16-year jail term.
Speaking before chairing a meeting of the Government’s emergency committee Cobra on Friday night, Prime Minister Boris Johnson said he had “long argued” that it is a “mistake to allow serious and violent criminals to come out of prison early and it is very important that we get out of that habit and that we enforce the appropriate sentences for dangerous criminals, especially for terrorists, that I think the public will want to see”.
Professor Stephen Toope, Vice-Chancellor of the University of Cambridge, said he was “devastated” that an event organised by its Institute of Criminology was targeted in the attack.
He said: “I am devastated to learn that yesterday’s hateful attack on London Bridge may have been targeted at staff, students and alumni attending an event organised by the University of Cambridge’s Institute of Criminology.
“We are in touch with the Metropolitan Police, and awaiting further details of the victims.
“We mourn the dead and we hope for a speedy recovery for the injured. Our thoughts are with all their families and friends.”
“Extensive cordons are likely to remain in place for some time and I would ask the public to continue to avoid the area.
“Public safety is our top priority and we are enhancing police patrols in the City and across London.”
Thomas Gray, 24, was among a group of men who dragged Khan to the ground near Fishmongers’ Hall.
The tour firm manager said he stamped on the terrorist’s wrist to try to make him release one of two large knives he was carrying.
Mr Gray told the PA news agency: “I was brought up on rugby and the rule is ‘one in, all in’. I did what any Londoner would do and tried to put a stop to it.”
The members of the public who intervened have been widely praised, with Mayor of London Sadiq Khan hailing their “breathtaking heroism” and Mr Johnson their “extraordinary bravery”.
The bridge was the scene of a terror attack in 2017 – also during a general election campaign – when eight victims were killed along with the three terrorists, who were also wearing fake suicide vests and armed with knives.