52-year-old British born Khalid Masood killed three people with his car, rented from Birmingham, where he lived, and a knife before being killed himself.
He was known to police for a string of convictions, including ones for assault, grievous bodily harm, and possession of offensive weapons, although none of these were terrorism-related.
He was not the subject of any investigations in the immediate lead-up to the attack.
Iwona Romek lived next door to Masood in Birmingham for five months until he suddenly moved just after Christmas.
She says he appeared to be a regular man.
Iwona Romek: "So he was a normal family man he used to take the child to school in the morning, taking care of his garden outside. I saw him many times cutting the grass and coming back from shopping."
