Prime Minister Boris Johnson has vowed to review Britain's sentencing system after a convicted terrorist released early from prison stabbed two people to death and injured three in a London Bridge attack.
Members of the public have been hailed as heroes for preventing even greater loss of life by tackling Usman Khan - one armed with a 1.5-metre narwhal tusk and another with a fire extinguisher - before police shot him dead.
Video footage of the confrontation showed Khan, 28, being challenged by a man, reportedly a Polish chef, wielding the tusk - believed to have been grabbed from the historic hall where the stabbings began - as another person sprayed him with the extinguisher.
The attacker, named by police as 28-year-old Usman Khan, was out of prison at the time of the attack. Source: Press Association
Khan had been conditionally released from jail last December after serving less than half of a 16-year prison sentence for terrorism and was wearing a fake explosive device.
"The person who carried out the London attack... was a fighter from the Islamic State, and did so in response to calls to target citizens of coalition countries," IS said, referring to a multi-country alliance against the group.
The incident comes two years after Islamist extremists in a van ploughed into pedestrians on London Bridge before attacking people at random with knives in nearby Borough Market.
On that occasion, eight people were killed and 48 wounded before the three attackers, who were wearing fake suicide devices, were shot dead by police.
British Prime Minister Boris Johnson with British Home Secretary, Priti Patel at the London Bridge crime scene. Source: EPA
Metropolitan Police Assistant Commissioner Neil Basu said five people had been stabbed in all inside Fishmonger's Hall before members of the public pursued the attacker onto London Bridge. The three survivors remain in hospital.
Mr Basu added that Khan had been released under "an extensive list of licence conditions" with which he had previously been complying.
Police on Saturday searched two properties in Stoke-on-Trent, Khan's home city, and Stafford in central England.
The latest attack came less than two weeks before Britain's general election, and politicians temporarily suspended campaigning.
"It does not make sense for us as a society to be putting people who have been convicted of terrorist offences... out on early release," Mr Johnson, who became Tory leader in July, said as he visited the scene.
A forensic search team attend a three-storey block of flats in Woverhampton Road, Stafford. Source: Press Association
"We argue that people should serve the tariff, serve the term, of which they are sentenced," the prime minister added, noting the Conservatives' manifesto called for a tougher sentencing regime.
