Westminster attack: Murdered officer named as PC Keith Palmer

An unarmed police officer who was among four people killed by a terrorist in Westminster has been named as PC Keith Palmer.

The 48-year-old husband and father was stabbed by a man armed with two knives in the grounds of the Houses of Parliament.

Moments earlier the assailant struck a number of pedestrians with a car on Westminster Bridge, before crashing the vehicle into railings outside Parliament. He was shot dead by armed police after attacking PC Palmer.

One of the three members of the public who died was hit by the attacker's car on Westminster Bridge.

Police say approximately 40 people were injured in the atrocity, some of whom were said to have sustained "catastrophic" injuries.

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Among those who rushed to help PC Palmer was Government minister Tobias Ellwood, who performed mouth-to-mouth resuscitation on the injured officer.

Paying tribute to PC Palmer, Met Police deputy commissioner Mark Rowley said: "He was someone who left for work today expecting to return home at the end of his shift - and he had every right to expect that would happen."

Conservative MP James Cleverly, who served with PC Palmer in the Royal Artillery, described the officer as "a lovely man".

He said: "I'm heartbroken. My thoughts are with the family, friends and colleagues of PC Keith Palmer. A brave man."

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London Mayor Sadiq Khan said the officer "personifies the brave men and women of our police and emergency services who work around the clock to keep us safe".

Theresa May has described the incident, which happened a year to the day after the Brussels attacks, as "sick and depraved" and praised the "exceptional bravery" of police and security services.

She also vowed that "the voices of hate and evil" would never be allowed "to drive us apart".

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Among those injured on Westminster Bridge were three police officers who were on their way back from a commendation ceremony. Two of them are in a serious condition.

Five South Koreans, three French youngsters on a school trip and two Romanians were also injured on the bridge, while a woman who fell into the Thames was rescued and given urgent treatment on a nearby pier.

Moments after the attack Parliament was placed on lockdown and the Prime Minister was bundled into a car as officers searched the building, evacuating floors one-by-one.

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Bomb squad officers were also called in to deal with a suspicious package found in a vehicle outside Parliament.

Metropolitan Police has deployed extra armed officers on the streets of the capital.

Meanwhile, Mr Rowley said the force "can call on the support of the military should we need to at a future point".

Both the House of Commons and the House of Lords will sit at their normal times later, less than 24 hours after the deadly attack.