Police later said Masood had no links to extremist groups such as al-Qaeda or the Islamic State, also known as ISIS.
An Australian was among those hospitalised, while a Spaniard escaped with light injuries.
"Two police officers remained in the back with him, and they had him lined across them and they placed pressure on the wounds and I'm trying to find those police officers now to say thank you", she told CNN. The wound missed her main arteries and windpipe, and she is said to be recovering well in hospital.
British police said on Sunday they would release the names of the three men who killed seven people in London "as soon as operationally possible", adding that searches were continuing in four properties.
A photo showed one suspect lying on the ground with the canisters on his belt.
"In two or five seconds, they shot all the three men down", Sciotto told the BBC. Our initial assessment is in the region of 50 rounds, in the region of 50 bullets were fired by those eight officers.
Giving an update on the investigation outside New Scotland Yard, the Met's assistant commissioner Mark Rowley said "significant progress" had been made in identifying the attackers. The BTP officer, who was on duty, was one of the first at the scene after he responded to calls for help from the public, the force said.
After the third militant attack in Britain in less than three months, May said Thursday's election would go ahead.
The country's major political parties temporarily suspended campaigning with only days to go before the general election.More news: Champions Trophy teams reassured over safety following Manchester terror attack
More news: Tiger Shroff, Nidhi Agerwal's 'Munna Michael' trailer out
More news: London terror attacks: ISIS claims responsibility
People in the United Kingdom have responded to the deadly London Bridge attack with sorrow and distinctly British humour, hailing a man pictured departing the mayhem while holding a pint of beer as a tongue-in-cheek symbol of heroism and defiance.
Trump said he had spoken with British Prime Minister Theresa May and offered the US' "unwavering support" in investigating the terror attacks at the iconic London Bridge and Borough Market in the heart of the British capital.
The attack in central London came just weeks after a suicide bombing at a concert in Manchester left 22 dead, and it recalled an attack in March when a man drove a auto into pedestrians near the seat of Parliament, killing five.
"Perpetrators are inspired to attack not only on the basis of carefully constructed plots ... and not even as lone attackers radicalized online, but by copying one another and often using the crudest of means of attack".
The pop star returned to the city amid heightened security last night for the One Love Manchester, charity concert to raise money for the victims of the attack.
Speaking outside 10 Downing Street, May warned there has been "far too much tolerance of extremism" in Britain.
Meanwhile, Prime Minister Theresa May called Sunday for tougher measures to contain Islamic extremism in Britain. "God Bless the Brits!"
"Volunteer your time and labour or donate to a homeless shelter", the statement said.
"The UK will observe a minute's silence on June 6 2017 and flags will remain at half-mast on Whitehall government buildings", said the statement.
Trudeau said that such hateful acts would not deter them and would only strengthen their resolve against terrorism.