Westminster attack: PC Keith Palmer named as police officer killed – as it happened

22 Mar 201712.35 EDT

Robert Booth

In Victoria Street teams of firefighters, some arriving in unmarked cars, have gathered and are pulling on burgundy overalls with the word “rescue” on the back. They appear to be wearing body armour and helmets and are moving towards parliament.

Speaking to reporters outside the central London hospital, junior doctor Colleen Anderson from St Thomas’ hospital has said a female pedestrian had died.

She also said she treated a police officer in his 30s with a head injury who had been taken to King’s College hospital.

She said: “I confirmed one fatality. A woman. She was under the wheel of a bus. She died, confirmed her death at the scene.”

Anderson said: “There were people across the bridge. There were some with minor injuries, some catastrophic. Some had injuries they could walk away from ...[others] have life-changing injuries. There were maybe a dozen [injured].”

London mayor Sadiq Khan has issued a statement. The London mayor said an urgent investigation is underway and his thoughts are with those affected and their families. He also expressed his thanks to the police and emergency services for their rapid response.

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22 Mar 201712.28 EDT

Vikram Dodd

A meeting of Cobra, the government’s crisis committee, is expected to meet later with senior officials from government, counter-terrorism officials and the police present.

The Labour MP Barry Sheerman has tweeted a series of pictures showing MPs locked in the Commons chamber.

22 Mar 201712.26 EDT

Ewen MacAskill

The intelligence agencies immediately put together teams to work on identifying who was involved in the attack and whether there was a link to a terrorist group.

If the attacker or attackers are from the UK, the domestic intelligence service MI5, which works closely with the police, will be looking at whether they were part of a wider network and working to track down associates.

The overseas intelligence agency MI6 will seek to establish whether there are any links to terrorists organisations in other countries.

One of the first questions raised will be whether the attacker or attackers had been under surveillance. The immediate response of the intelligence agents would be that if they had someone under surveillance and became aware an attack was imminent, they would have stepped in. But MI5 does not have the resources to maintain 24-hour surveillance on all possible suspects and has to make hard choices about who poses the highest risk.

Although symbolically parliament is one of the most high-profile targets in the UK, it is also one of the most heavily guarded. Without the high level of security, the casualty list could have been much higher.

22 Mar 201712.23 EDT

Severin Carrell

Holyrood’s sitting to debate Nicola Sturgeon’s independence referendum demand was suspended at just after 15.55, after parliament authorities reversed an earlier decision to keep sitting.

About 20 minutes after his deputy Linda Fabiani told MSPs it would be “business as usual”, Ken McIntosh, the Scottish parliament’s presiding officer, told MSPs he was postponing the debate out of respect for Holyrood’s “sister parliament”. He said:

Members will know that there has been a serious incident at Westminster and Westminster has been locked down because of security concerns. I have certainly no reason to cause undue alarm here and security has been increased here.

22 Mar 201712.23 EDT

Robert Booth

Mike Jephcott, 38, was working at the Royal Institute of Chartered Surveyors which overlooks Parliament Square when he heard three gunshots.

“I looked at my colleague and said ‘I’m sure that’s gunshots’. There was panic and people running around,” he told the Guardian. “Police were running around.”

“We saw the car on the side down by Big Ben. It was quite scary. Our offices were on lockdown and we have been asked to evacuate now.”

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22 Mar 201712.19 EDT

Luke Harding

More from Kirsten Hurrell, who witnessed the incident from her newspaper kiosk in Parliament Square. (See 3.51pm.)

Hurrell said that the car had come to a halt following shots.

“There were shots to stop the car. The car turned, went completely over the cycle lane and rammed nose-first into the parliamentary fence. There was someone on the ground on the right of the car. They didn’t look very good.”

Hurrell said her family had had her Newsstand kiosk for nearly 100 years. “I’m not surprised by what happened,” she said. “This was always potentially a hot spot. I lived through the IRA incidents. We have got a lot of experience with terrorism. With what’s going on in the world it’s not surprising.”

The emergency services had responded amazingly, she said. “They were magnificent. Quick to respond and quick to evacuate.”