Censor.NET reports referring to the Metropolitan police website.
The man has been formally identified as Khalid Masood, 52, born in Kent. Detectives believe he was most recently living in the West Midlands.
Masood was not the subject of any current investigations and there was no prior intelligence about his intent to mount a terrorist attack.
However, he was known to police and has a range of previous convictions for assaults, including GBH, possession of offensive weapons and public order offences.
His last conviction was in December 2003 for possession of a knife.
Masood has not been convicted for any terrorism offences.
As reported, four people were killed and dozens injured as a result of shooting on Westminster Bridge near the British Parliament on March 22.
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