London attack as it happened: Five dead and 40 injured after terror incident in Westminster

Westminster terror attack: Timeline of events

A police officer has been stabbed and an alleged assailant shot by armed police outside the Houses of Parliament.

Here's what we know so far:

• Police officer died after being stabbed outside Parliament
• Two people reported dead after a car ploughed into crowd on Westminster bridge causing multiple casualties
• Metropolitan police are treating this as a terrorist incident
• Eyewitness account of the stabbing incident outside Parliament gate
• Donald Trump has been briefed on the attack, Sean Spicer confirms
• Theresa May was '40 yards away' from scene of stabbing, was immediately evacuated and confirmed safe
• House of Commons session suspended and MPs evacuated

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Commons Leader David Lidington has told MPs a "police officer has been stabbed" and the "alleged assailant was shot by armed police" following a "serious" incident within the parliamentary estate.

Minutes later, an emergency services helicopter landed in Parliament Square, as sirens were heard outside.

Iframe:

Air ambulance medics came from the helicopter to assist the casualties.

A woman was confirmed dead after a car ploughed into corwds on Westminster Bridge causing multiple casualties (Reuters)

Two people lay on the ground in the yard. One of them appeared to have had clothes removed as emergency workers attempted to resuscitate the pair.

Parliament Square was closed to traffic.

[22 March 2017 16:32 · Andrew Griffin]

The person seen in the river has been recovered alive, according to officials.

A spokesman for the Port of London Authority, which looks after safety on the River Thames, 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. We believe she fell from the bridge."

He said the river has been closed from Vauxhall to Embankment "as part of the security response".

[22 March 2017 16:35 · Andrew Griffin]

A Holyrood vote expected to back Nicola Sturgeon's calls for a second Scottish independence referendum has been put on hold following the terror attack in Westminster.

The Scottish Parliament suspended business in the wake of the incident at the Houses of Parliament, where an attacker stabbed a policeman before being shot by officers.

MSPs had been due to vote on whether the Scottish Government should seek discussions with the Conservative administration at Westminster on the details of a section 30 order - the legal mechanism that would allow a second independence ballot to be held.

But with business in Holyrood suspended, that will now take place later.

[22 March 2017 16:37 · Andrew Griffin]

Labour MP Mary Creagh told reporters: "They are clearing it floor by floor."It was very frightening, to see people running towards you, to hear that shots had been heard.""My thoughts are really with those people" who were victims of the attack, she said.

[22 March 2017 16:37 · Lizzie Dearden]

Police are treating Westminster as a terror incident, please send any pictures or video toukpoliceimageappeal.co.uk

[22 March 2017 16:38 · Andrew Griffin]

A second person has died, according to reports.

[22 March 2017 16:41 · Andrew Griffin]

Here is a full rundown of the existing security measures, provided by the Press Association. It's obviously likely that more will go into effect once the incident is over.

:: There are a number of entrances onto the parliamentary estate for staff and visitors but all are subject to security measures.

:: Visitors can enter through the Cromwell Green entrance and through the main doors at Portcullis House. Both entrances have airport-style security.

:: There are a number of entrances for holders of parliamentary security passes, MPs, palace staff etc, which are required to gain access to any one of the entrances. Armed police are stationed at all of the main entrances.

:: Armed police officers are always stationed on the Carriage Gates which is the main road entrance into Parliament. The entrance is always blocked by metal barricades and there are also car park-style barriers for vehicles on the way in and out of the palace.

:: Armed police are stationed throughout the palace itself.

:: Sniffer dogs are often seen on the parliamentary estate carrying out checks, including before major events such as Prime Minister's Questions.

:: Security incidents have occurred on the parliamentary estate over the years, most notably when Prime Minister's Questions was halted in May 2004.

:: This occurred after Fathers 4 Justice campaigners threw condoms filled with purple flour and glitter at Tony Blair, although it initially sparked fears that the Commons was under biological attack.

:: A glass screen was installed in the public gallery to prevent similar incidents.

:: An increased focus on the security of MPs emerged following the murder of Labour MP Jo Cox in her Batley and Spen constituency in June 2016.

:: A police hotline was set up for MPs to report threats made against them.

:: Figures released this week showed a specialist police team set up to investigate crimes against MPs, the Met's parliamentary liaison and investigation team, has probed more than 50 complaints in the six months of Mrs Cox's murder.

[22 March 2017 16:45 · Andrew Griffin]

Staff from the Treasury are now being sent home, according to Independent journalist Matthew Murphy who is at the scene. They are being told to hide their passes as they do so, he says.

[22 March 2017 16:46 · BBCPeterH]

Bournemouth MP @Tobias_Ellwood helped injured policeman in Parliament - gave mouth-to-mouth. His brother was killed in Bali terrorist attack

[22 March 2017 16:48 · Andrew Griffin]

"We know there are a number of casualties including police officer," said Commander BJ Harrington from the Met Police during a press conference just now. "But at this stage we cannot confirm numbers or the nature of these injuries."

[22 March 2017 16:52 · Andrew Griffin]

Prime Minister Theresa May will chair a meeting of the Government's emergency Cobra committee later today, a Downing Street spokesman said.