Police have named Khalid Masood as the man who attacked Parliament yesterday.
Masood, who was shot dead after attacking a policeman with a knife outside the House of Commons, was 52 and from Kent.
He had a string of previous convictions ranging from GBH to possession of offensive weapons.
He had not been convicted of any charges relating to terrorism and Scotland Yard have said he was not subject to any ongoing investigations.
London remains in shock after yesterday's attacks, in which a car was driven into pedestrians on Westminster Bridge before the attacker emerged from the vehicle and stabbing the policeman, who subsequently died.
Islamic State has claimed responsibility for the attack, but this has been disputed by terror and extremism expert Jonathan Russell, who spoke to Julia Hartley-Brewer on talkRADIO this morning.
Russell said Isis probably didn't know of the attack until the rest of the world did, and were simply trying to gain publicity by claiming they were behind it.