AS IT HAPPENED: Four dead after attack near London's Houses of Parliament

Four people have died in what police are calling a terror attack in the heart of London's Westminster.

Britain's parliament went into lockdown on Wednesday after a police officer was stabbed and an alleged assailant ploughed down pedestrians on one of London's busiest bridges.

WHAT WE KNOW

  • Suspect mowed down ten pedestrians in Hyundai 4x4 on Westminster Bridge;
  • Decamped and stabbed to death a police officer;
  • Four people dead, including police officer, two members of the public and alleged assailant;
  • Forty believed injured, including three police officers
  • House of Commons locked down.
  • Trevor Brooks, widely reported to be the suspect, "is still in jail and did not carry out London attack".
A woman assists a person injured in the attack in London on Wednesday. Photo: Reuters

STORIES:
'There was so much blood': Witnesses recall sickening London terror scenes
'Absolute hero': MP's desperate bid to save slain police officer
Outpouring of love following London terror

9.30pm: Police have revised the death toll to four, down from the five police reported earlier.

Meanwhile, 29 are being treated in five hospitals across London, with seven in a critical condition, Mark Rowley, acting deputy commissioner at the London Metropolitan Police, told a news conference tonight.

3.36pm:

Here's a visual recap of the devastating London terror attack:

In pictures: Scenes of devastation as London targeted in terror attack

3.30pm: As the western world comes to grips with the reality of the London terror attack, a photograph of a woman at the scene walking past a victim while on her phone, has sparked a passionate debate on social media.

It’s unknown who the woman was speaking to or what her intentions were, however Twitter user Texas Lone Star ignited the fury by tweeting the photo with the caption: “Muslim woman pays no mind to terror attack, casually walks by a dying man while checking phone”.

FULL STORY: Photograph of woman at scene of London Terror attack sparks passionate online debate

3pm: London photographer Toby Melville described the moment he “heard a thud” after a man was sent flying off the bridge.

"I heard a thud, turned round and there was a man lying about 10 yards away from me," he wrote.

"There was a lot of blood coming from his head. I thought this must be a domestic or horrible accident.”

FULL STORY: 'There was so much blood': Witnesses recall sickening London terror scenes

2.45pm:

Attacks near London's Westminster Palace feel very close to home for New Zealanders who have visited and called the city home, Prime Minister Bill English says.

In a statement Mr English has condemned the attacks that left five people dead, including a police officer and the alleged assailant on Wednesday (local time).

"Innocent people should never have to fear such violence when going about their daily lives, and New Zealand stands alongside the UK in the fight against terrorism and violent extremism," he said on Thursday morning.

"Our thoughts are with the people of London, and in particular with the victims of today's shocking attack, and their families and friends," Mr English said.

While Australian authorities have stepped up security at Parliament House in Canberra, Deputy Prime Minister Paula Bennett said she feels safe with the current security measures in Wellington.

"We're always conscious that it's an unsettled world out there and we're part of it, but I don't think we need to be unduly worried," she said.

"I think we've got good security around here, we are watching those that we think might be dangerous - that's part of our security arrangements - and I certainly feel confident being here."

Parliamentary Services in Wellington believe there is no increased threat in New Zealand.

"Established processes are in place to continuously assess security threat levels at Parliament. Our current assessment is there is no increased threat to New Zealand's Parliament," a spokesperson told NZ Newswire.

The Ministry of Foreign Affairs and Trade believes no New Zealanders were caught up in the attack.

"We advise New Zealanders in London to avoid the Westminster area, follow any instructions issued by the local authorities and let family in New Zealand know they're safe and well," an MFAT spokesman said.

2.37pm: US President Donald Trump's son has today criticised the mayor of London in the immediate aftermath of the attack.

"You have to be kidding me?!" Donald Trump Jr. tweeted, as he shared an article from The Independent, and paraphrased its headline as: "Terror attacks are part of living in big city, says London Mayor Sadiq Khan".

2.29pm: Two of the three injured police officers are in a serious condition.

Another officer, Keith Palmer, who lost his life in the attack was unarmed when he was targeted.

Assistant Commissioner Rowley said police are operating under the assumption that the attacker was "inspired by international terrorism".

2.17pm: A woman, believed to have fallen from Westminster Bridge during the “terror attack”, is fighting for life after being pulled from the River Thames.

A Port of London Authority spokesman told the Evening Standard the woman was rescued just before 3pm local time.

“A female member of the public was recovered from the water near Westminster Bridge.

“She is alive but undergoing urgent medical treatment on a nearby pier.

“We believe she fell from the bridge," the spokesperson said.

Footage has been released that shows a woman falling into the River Thames as a car speeds across Westminster Bridge.

2.15pm: London police are investigating the motivation of the attacker, and are researching his background and his family.

Officers have confirmed that they know who the man is, but said they will not be identifying him.

They have asked the media to stop speculating about his identity.

Police said they are also investigating his associates.

An injured person is treated at the sight of the London terror attack. Photo: AAP

1.14pm Statement from London's top anti-terror officer Mark Rowley says working assumption is the perpetrator in Wednesday's attack was "inspired by international terrorism".

According to the Standard, the spokesman said: “A female member of the public was recovered from the water near Westminster Bridge.”

“She is alive but undergoing urgent medical treatment on a nearby pier,” the Standard reported the spokesman as saying.

“We believe she fell from the bridge.”

Footage has been released that shows a woman falling into the River Thames as a car speeds across Westminster Bridge.

12.36pm

The Eiffel Tower has gone dark in mourning and solidarity with Britain after an attack around the British Parliament in which four people, including the attacker, were killed.

Paris Mayor Anne Hidalgo, whose city has suffered deadly extremist attacks in recent years, announced that the tower is turning off its twinkling lights at midnight.

Three French teenagers on a school trip were among those injured in Wednesday's attack targeting pedestrians on London's Westminster Bridge and a police officer on the nearby Parliament grounds.

French President Francois Hollande has offered support for Britain and the investigation.

12.28pm

The mayor of London, Sadiq Khan, has posted a statement regarding the death of police officer Keith Palmer.

"PC Keith Palmer was killed doing his duty - protecting our city and our democracy from those who want to destroy our way of life," he wrote.

"My heart goes out to his family, friends and colleagues."

Source: Facebook/Mayor of London

11.54am Footage has been released that shows a woman falling into the River Thames as a car speeds across Westminster Bridge.

11.33am The police officer who died has been named as Keith Palmer, of the Diplomatic Protection Service. He was 48 and a husband and father.

11.32am The death toll from the terror attack in London has risen to five, while 40 now are believed to be injured.

11.20am

A London MP has been dubbed a hero after desperately applying first aid to a victim killed in Wednesday's London terror attack.

Photo: Supplied

Foreign Office Minister Tobias Ellwood emerged from a sea of paramedics with blood smeared across his face after giving mouth-to-mouth resuscitation to a man believed to be the police officer that was fatally stabbed.

MORE: Heroic MP's desperate bid to save slain police officer

10.16am

9.53am

9.23am The Ministry of Foreign Affairs and Trade says there's no indication any New Zealanders were caught up in the incident.

"We advise New Zealanders in London to avoid the Westminster area, follow any instructions issued by the local authorities and let family in New Zealand know they're safe and well," an MFAT spokesman said.

9.07am Pauline Cranmer, London Ambulance Service's deputy director of operations, issued this statement:

“Our thoughts are with the friends and families of those affected by today’s incident.

"We treated 12 patients for serious injuries, who were all taken to hospital. Eight further patients were treated for less serious injuries at the scene. Sadly, three people also died at the scene."

8.55am BBC journalist Dominic Casciani tweets that Trevor Brooks, also known as Abu Izzadeen, a hate preacher widely reported to be the attacker, is still in jail and is not behind the attacks.

8.53am Statement from Guy's and St Thomas' NHS Foundation Trust says: "Two patients are being treated at St Thomas' Hospital following today's security incident at Westminster - one man and one woman ... both are in a stable condition."

8.52am London mayor Sadiq Khan says the city will never be cowed by terrorism.

8.22am

8.13am Both houses of the British parliament will sit as usual on Thursday, officials said, following an attack outside the building on Wednesday in which four people died.

"We can confirm that both the House of Commons and the House of Lords will sit tomorrow at their normal times," the parliament Twitter feed said.

8am Londoners are taking to Twitter to show their defiance:

7.58am Investigators are considering the possibility that the attack on the British parliament was inspired by Islamic State propaganda, a European government official told Reuters.

British investigators have some leads on the identity of the attacker who was shot but have not yet confirmed all the details, according to the official, who spoke on condition of anonymity.

7.52am Canning Town tube station in east London reopens after "security alert".

Westminster Bridge. Photo: AP

7.49am Canada Prime Minister Justin Trudeau tells UK citizens and colleagues in British Parliament: "We stand with you."

7.36am The car continued speeding and just started taking people off ... It was a horrible sight ... It was all deliberate," one eyewitness tells Sky News in the UK.

7.21am U.S. Secretary of State Rex Tillerson condemned Wednesday's attack outside parliament in London and expressed his condolences to the victims and their families.

"We condemn these horrific acts of violence, and whether they were carried out by troubled individuals or by terrorists, the victims know no difference," he said in a statement.

7.15am Canning Town tube station in East London is closed down due to "security alert", according to Transport for London.

7.01am Scotland Yard confirms four people are dead after the attack.

7am Police are still searching for one of the two people believed to have launched Wednesday's attack outside the British parliament building, assistant editor of the Daily Telegraph newspaper Christopher Hope tweeted, citing senior government sources.

A BBC journalist said two assailants were believed to have been in a vehicle involved in the attack.

"BBC understands from multiple sources two assailants in vehicle on Westminster Bridge," BBC correspondent Dominic Casciani said on Twitter.

6.51am A woman has been pulled from the River Thames alive after Wednesday's attack on a bridge near Britain's parliament in Westminster, the Port of London Authority (PLA) said, adding that she was being treated for serious injuries.

"A female member of the public was pulled from the water near Westminster Bridge, alive, with serious injuries," a PLA spokesman told Reuters.

"She's undergoing very urgent medical treatment now."

He added that the river had been closed to all non-emergency traffic in the immediate area.

Armed police swarm the scene near Westminster as the injured are treated. Photo: AP

6.50am Three French schoolchildren were hurt in the attack near London's parliament on Wednesday, French officials said.

The three were students aged around 15 or 16 of the Concarneau Lycee in Brittany, western France, according to a report in Le Telegramme regional newspaper.

Prime Minister Bernard Cazeneuve confirmed on Twitter that the three were schoolchildren.

The report in Le Telegramme cited a fellow students who was at the scene of what British police have described as a terrorist incident, saying the three were hit by a car that was involved whilst walking on Westminster Bridge.

6.40am French Prime Minister confirms that a number of French students were injured in the attack in London.

6.37am Member of Parliament Tobias Ellwood confirms a police officer died at the scene, local media reports.

Unconfirmed media reports said the attacker mowed people down on the bridge in a car before veering towards the parliament building and ramming the railings surrounding the grounds.

He got out and attacked the police officer before he was shot.

British police said there had been an unspecified number of casualties including police officers.

Sky News said on Twitter, citing unspecified sources, that two people have died.

Reports said the attacker was carrying a large knife.

One woman was killed, according to medics cited by local media, and several suffered "catastrophic" injuries.

In quick succession at about 2.40pm local time on Wednesday (3.30am Thursday NZT), media reported gunfire outside the parliament and, separately, that several people had been injured in an incident on Westminster Bridge next to it, a busy traffic conduit that is also a popular tourist spot due to its views of parliament and its "Big Ben" clock tower.

There has been an unspecified number of injuries, including police officers. Photo: AP

David Lidington, a government minister who is the leader of the lower House of Commons, told the chamber that a police officer had been stabbed on the parliamentary estate and that armed police had shot the alleged attacker in response, adding that there had been "reports of further violent incidents in the vicinity".

Parliament was put on lockdown, with lawmakers and staff ordered to remain inside.

"We know there are a number of casualties including police officers but at this stage we cannot confirm numbers or the nature of these injuries," Commander BJ Harrington told reporters.

"We received a number of different reports which included a person in the river, a car in collision with pedestrians and a man armed with a knife."

He said the acting head of London police, Craig Mackey, was being treated as a significant witness as he was at scene when the incident took place. He was not one of those injured.

Downing Street said Prime Minister Theresa May was safe, and she was seen getting into a car and being driven away from the parliament where she had been holding her weekly question-and-answer session a couple of hours earlier.

Television pictures showed a red air ambulance landing on the grass square opposite the parliament building and other emergency vehicles swarming nearby roads.

Westminster Bridge and the Westminster Underground station which serves parliament and the surrounding political district, were closed off.

Witness reports, which could not be immediately confirmed, described a middle-aged man of Asian appearance who was carrying a large knife.

London's transport system was hit by four co-ordinated suicide bomb attacks in July 2005 that left 52 people dead, carried out by British attackers inspired by Al-Qaeda terror network. There was an attempted second wave of attacks two weeks later.

In 2013, two Islamic extremists killed soldier Lee Rigby on a London street by hitting him with a car before attempting to behead him.

Last August, a paranoid schizophrenic knifeman who tried to behead a commuter in a London Underground station in an Islamic State-inspired attack was sentenced to life behind bars.

In terms of attacks on parliament, Airey Neave -- the shadow Northern Ireland Secretary and a close friend of Conservative Party leader Margaret Thatcher -- was killed by an Irish National Liberation Army car bomb in the House of Commons car park.??

The latest incident comes with Europe on high alert after a series of deadly jihadist attacks, including the Brussels bombings exactly a year ago on March 22, 2016.