What we know about the London attack so far: 2 attackers ID'd

Seven people, including one Canadian, were killed by attackers who drove a van at high speed into pedestrians on London Bridge and then stabbed revellers in the nearby Borough Market area on Saturday night.

It was Britain's third militant attack in as many months and took place five days before the upcoming national election on Thursday, June 8, which British Prime Minister Theresa May said would go ahead as planned.

May said the perpetrators were Islamist militants and called for a tougher counterterrorism strategy. All three attackers were shot dead by police within minutes of the first emergency call being made.

Here's what is known about the attack so far:

How did it unfold?

The attack started at 9:58 p.m. local time, Mark Rowley, Britain's top counterterrorism police officer, said.

Three attackers drove a hired white Renault van at high speed, from north to south, into pedestrians walking on London Bridge, police said. Rowley said the van had been recently hired by attackers.

A witness said at least six people were hit on the bridge.

"It looked like he was aiming for groups of people. I froze because I didn't know what to do," Mark Roberts, a 53-year-old management consultant, told Reuters. "It was horrendous."

Police said they responded to the incident on London Bridge at 10:08 p.m.

The three men then abandoned the vehicle, ran down a set of stairs and began attacking people with knives in the nearby Borough Market area on the south side of the Thames River, police said.

The neighbourhood is best known for its 1,000-year-old food market but is also home to many popular pubs and restaurants. Witnesses said the attackers stabbed people in the street, as well as those in pubs and restaurants.

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"Armed response officers then responded very quickly and bravely and confronted the three male suspects, who were shot and killed on Borough Market," Rowley said. "The suspects were wearing what looked like explosive vests but these were later established to be hoaxes."

Rowley said that eight officers fired about 50 bullets at the men — an "unprecedented" amount for British police. A member of the public received a non-critical gunshot wound as a result, he added.

One of the attackers was shown in a photograph lying on the ground outside the Wheatsheaf pub. Another man, also reported to be an attacker, was pictured on the ground a short distance away.

"We believe that the threat that they posed was neutralized in eight minutes," Metropolitan Police Commissioner Cressida Dick told reporters.

Who was involved in the attacks?

London Metropolitan Police said in a statement Monday they strongly believe two of the men are Khuram Shazad Butt and Rachid Redouane, both from Barking, east London.

Butt, 27, was a British citizen born in Pakistan. Redouane, 30, had claimed to be Moroccan and Libyan and also used the name Rachid Elkhdar.

Only Butt was known to police and British intelligence agency MI5, according to the statement, but "there was no intelligence to suggest that this attack was being planned."

Police said formal identification of the bodies has yet to take place, and they are still working to confirm the identity of their accomplice.

Police detained 12 people — seven men and five women — in the Barking area in their investigation. Two have since been released.

U.K. Prime Minister Theresa May earlier said the attacks were inspired by what she called a "single, evil ideology of Islamist extremism" that represented a perversion of Islam and of the truth.

May said there was no direct relationship between the London Bridge attack, the suicide bombing at a concert in Manchester that killed 22 people two weeks ago and another vehicle and knife attack in Westminster in March which killed five people.

She called for a review of counterterrorism strategy.

"We believe we are experiencing a new trend in the threat we face, as terrorism breeds terrorism, and perpetrators are inspired to attack not only on the basis of carefully constructed plots after years of planning and training — and not even as lone attackers radicalized online — but by copying one another and often using the crudest means of attack," she said.

Mark Rowley, assistant commissioner of the London police, said in the statement identifying the suspects on Monday that the counterterrorism front involves prioritizing a large number of files.

"At any one time, MI5 and police are conducting around 500 active investigations, involving 3,000 subjects of interest. Additionally, there are around 20,000 individuals who are former subjects of interest, whose risk remains subject to review by MI5 and its partners," said Rowell.he SITE Intelligence Group said on Sunday ISIS claimed responsibility for the attack.

SITE said in a statement that the Islamic State in Iraq and Syria's Aamaq news service cited "a security source" in the Arabic-language posting claiming the attack.

Who are the victims?

Seven people were killed in the attack, including one Canadian and one French citizen.

Christine Archibald, from Castlegar, B.C., was struck on London Bridge, where she was walking with her fiancé, according to the fiancé's siblings. A statement from her family recalled the 30-year-old as someone with a big heart, who had been working in a homeless shelter before she moved to Europe.

"We grieve the loss of our beautiful, loving daughter and sister. She had room in her heart for everyone and believed strongly that every person was to be valued and respected," the statement read. "She would have had no understanding of the callous cruelty that caused her death. Please honour her by making your community a better place."

The sister of a missing 32-year-old Briton says he is believed to have died in the attacks.

Melissa McMullan told Sky News on Monday that police said her brother James McMullan's bank card was found on one of the bodies after the attack, which claimed seven victims.

McMullan says her brother was last seen outside a pub just before the van and knife attacks began.

A French national was also among the victims, the country's foreign ministry said, while Spanish officials say a 39-year-old man who was in the Borough Market on Saturday night near the attack is missing.​

Forty-eight others were wounded in the attacks, and the English health authority said Monday that 18 people remained in critical condition.

What are the political implications?

The U.K. is due to hold a national election on Thursday, and officials said the vote would not be postponed.

Major political parties suspended national campaigning in the immediate wake of the attack, with the exception of the anti-European United Kingdom Independence Party.

The May-led Conservatives were far ahead in polls, but their lead has narrowed in recent days.

Saturday's attack came less than two weeks after suicide bomber Salman Abedi blew himself up at a concert in Manchester on May 22.

Britain raised its terror threat to the highest level of "critical" and deployed troops on the streets on May 23, a day later. The critical level means another attack is "expected imminently." It was reduced on May 27 to "severe," which means an attack is "highly likely," and the prime minister said Monday it will remain there for the time being.

Also, on March 22, Khalid Masood plowed a rented car into pedestrians on Westminster Bridge in London and stabbed a policeman to death before being shot dead. His attack killed five people.

May said Sunday that police had recently foiled five other plots.