A police officer who was among four victims of a terror attack 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 and another officer
Police say approximately 40 people were injured in the atrocity, some of whom were said to have sustained "catastrophic" injuries.
Among those who rushed to help PC Palmer outside Parliament 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."