EDITOR’S NOTE: This post has been updated to clarify the number of causalities after police revised the death toll from five to four.
At least four people were killed, including a police officer, and at least 40 others injured in what police have declared a “terrorist incident” outside of the U.K. Parliament Wednesday.
London’s Metropolitan Police said a vehicle struck a number of people around 2:40 p.m. local time, including three police officers walking on the Westminster Bridge, not too far from where a police officer was stabbed outside of the British Parliament.
WATCH: Video coverage of ‘terror incident’ in London
“The car then crashed near to Parliament and at least one man armed with knife continue the attack and tried to enter Parliament,” Deputy Police Commissioner Mark Rowley said.
The attacker was then shot dead by police.
In a statement later on that night, Rowley confirmed the number of dead rose to five. However, police again later clarified the number of causalities were in fact four, including the attacker.
“One of those who died today was a police officer,” Rowley told reporters. The officer was identified as 48-year-old Keith Palmer, who was protecting Parliament at the time of the attack.
“I can also now confirm that three members of the public who lost their lives in the attack. … and as I confirmed earlier, the suspected attacker was shot dead by an armed officer.”
Two other police officers remain in serious condition, Rowley confirmed.
Rowley said officers believe there was only one attacker, adding that it’s still under investigation.
“Our working assumption is that he was inspired by international terrorism,” Rowley said.
Police are currently focusing on the unnamed suspect’s motivation, preparation and whether or not he had associates.
“We are satisfied at this stage that it looks like there was only one attacker. But it would be foolish to be overconfident early on,” Rowley had said earlier Wednesday.
He also said the number of officers on the streets in London will be higher than normal for the next few days.
A house in Birmingham was raided by police early Thursday morning, reportedly in connection with Wednesday’s attack.
BBC reports that the house might have been linked to the car used in the rampage. Witnesses said they saw people removed from the house, the Daily Telegraph reports.
An Associated Press photographer captured the moment, seen in the photo below, when a police officer appears to be pointing a gun at a man being worked on by paramedics.
The man was then put on a stretcher and taken to an ambulance.
Police have declared the attack as a “terrorist incident.”
“Our response will be ongoing for some time as it is important that we gather all the possible evidence.” Commander BJ Harrington said.
The police commander noted that “although we remain open minded to the motive, a full counter-terrorism investigation is already underway, led by the Met’s Counter Terrorism Command.”
Speaking with the Associated Press, a witness said he saw a man stab a police officer outside of the Parliament building.
“We were just walking up to the station and there was a loud bang and a guy, someone, crashed a car and took some pedestrians out,” Rick Longley told the news agency. “They were just laying there and then the whole crowd just surged around the corner by the gates just opposite Big Ben.
“A guy came past my right shoulder with a big knife and just started plunging it into the policeman.”
French Prime Minister Bernard Cazeneuve said on Twitter that French students were among the injured.
Speaking with Sky News, a witness said she saw a car “go out of control and go into pedestrians on the bridge.”
“I saw people lying on the floor, obviously injured. I saw about 10 people, maybe,” the woman told the broadcaster.
Prime Minister Theresa May was safe after the incident, a spokesperson said in a statement.
May addressed the attack later on Wednesday and said the suspects behind the “sick and depraved” terrorist attack purposely chose to “strike the heart of [the] capitol” because it thrives on democracy and freedom of speech.
The Westminster tube station was also closed due to the police investigation.
The mayor of London issued a statement saying an “urgent investigation is underway” and his “thoughts are with those affected and their families.”
Canada’s Public Safety Minister Ralph Goodale says he’s spoken with British Home Secretary Amber Rudd to offer Canada’s assistance.
He says there’s no change in the threat level in Canada, but he says Canadian security agencies are taking all appropriate steps.
Canadian Prime Minister Justin Trudeau expressed his condolences to the “victims of this cowardly attack.”
“The scene unfolding in London is one that is all too familiar to members of this House that were here two and half years ago,” Trudeau said in the House of Commons. “An attack on the symbol and the seat of democracy is a cowardly and reprehensible act that we condemn in the strongest terms.
“Canada and the U.K. are close friends and allies and our message to the citizens of the United Kingdom and our colleagues in the British parliament is simple. We stand with you,” the prime minister said.
In 2014, gunman Michael Zehaf Bibeau fatally shot Cpl. Nathan Cirillo at the National War Memorial in Ottawa before storming Parliament Hill where he died in a shootout with then House of Commons Sergeant-at-Arms Kevin Vickers.
U.S. Secretary of State Rex Tillerson issued a statement Wednesday afternoon condemning the attacks.
“We condemn these horrific acts of violence, and whether they were carried out by troubled individuals or by terrorists, the victims know no difference,” Tillerson said.
Wednesday’s incident comes on the one-year anniversary of the terror attack in Brussels during which suicide bombers killed 32 people in an airport and metro station. Britain’s terror alert level remains “severe” or “an attack is highly likely,” which was last updated in May of last year.
British ex-pats living in Canada are reeling after a day like today.
Simone Hodgkinson, who owns The British Chippy restaurant near Calgary, says she finds it hard to concentrate on her duties.
“Well you know you’re always shocked, and certainly panicked, and it makes me feel like a long way from home, and just worried,” said Hodgkinson.
“I’m trying to hold it together. I’ve got my job to do and I’ve got people to serve, and I’ve got a smile to put on my face, but I’m worried,” she said.
“I don’t like to hear things like this in any part of the world, and when it’s close to home and you’re not there, it’s hard.”
Emma Goymer, a British citizen from Surrey, a county not far from London, said news of the Westminster attack spread quickly through her social network.
“My friend texted me, and she’s British as well. She lives here. It’s just a shock to hear that, you know, your family’s so close,” Goymer said.
Brenda Cahill was also surprised to learn of the attack in her home country.
“[I] just feel very worried for everybody over there. It’s terrible, you just feel so sad, because Britain welcomes in so many people into its shores, and it’s just not right,” Cahill said.
And for Hodgkinson, there’s a sense of guilt over the security she enjoys here.
“I love Canada for its safety, and I almost feel wrong for being here, feeling safe, if I’ve got family members who are not feeling so safe right now.”
*with files from David Boushy and the Canadian Press
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