Authorities in London have identified the man who killed three people outside the British Parliament building on Wednesday as Khalid Masood, a 52-year-old born in England. He was not on any terrorist-watch list, though he did have numerous arrests on his record.

"Masood was not the subject of any current investigations and there was no prior intelligence about his intent to mount a terrorist attack," according to Scotland Yard. "However, he was known to police and has a range of previous convictions for assaults, including grievous bodily harm, possession of offensive weapons and public order offenses."

One American was among those killed on Wednesday. Kurt Cochran, from Utah, was visiting London with his wife (who survived) for their 25th wedding anniversary. The two other victims were an unarmed constable, Keith Palmer, whom Masood allegedly stabbed before being fatally shot by police, and a mother-of-two named Aysha Frade.