The police officer killed outside Parliament has been named as Keith Palmer.

The 48-year-old, a husband and father, was stabbed with two knives by the unamed attacker who was then shot dead by police.

The death toll from the terror attack now sits at five.

Three pedestrians were mowed down on Westminster Bridge when the attacker mounted a pavement in a Hyundai 4x4.

In a statement late tonight, Acting Deputy Commissioner Rowley paid tribute to his colleague: "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."

It has been revealed t hat 40 others are injured.

He added: "Today, in Westminster we saw tragic events unfold and our thoughts are with those who lost loved ones, who were injured, and all those affected by this attack.

"One of those who died today was a police officer – PC Keith Palmer – a member of our Parliamentary and Diplomatic Protection Command.

"Keith – aged 48 – had 15 years’ service and was a husband and a father."

Conservative MP James Cleverley said he had known Mr Palmer for 25 years and used to serve with him in the Royal Artillery.

He Tweeted: ‘I’ve known Keith for 25 years. We served together in the Royal Artillery before he became a copper. A lovely man, a friend. I’m heartbroken."

Craig Mackay, acting Met Commissioner, who was standing with the three officers on the bridge is believed to be acting as a "significant witness".

The group were returning from a commendation ceremony at the time of the attack.