Surveillance video shows people running out of a Chick-fil-A after police said an off-duty officer shot and killed a man chasing two people with a knife.

Security footage obtained by the Globe shows a panicked crowd fleeing the Chick-fil-A restaurant in Copley Square Saturday evening at about the time an off-duty police officer shot and killed a person police say was wielding a knife and trying to stab people.

The knife-wielding attacker shot and killed by an off-duty Boston police officer after refusing to back down from terrorizing Chick-fil-A patrons in the Back Bay this weekend has been identified.