BOSTON — A video of the police shooting a terrorism suspect here last week shows six law enforcement officers approaching the man before they retreat and then fatally shoot him.

The video, shown last week to clergy members, civic leaders and the family of the suspect, Usaamah Rahim, was released Monday to the public. It was taken from a Burger King surveillance camera in a parking plaza about 50 yards from where the shooting occurred last Tuesday in the Boston neighborhood of Roslindale.

The footage, less than a minute long, is blurry, and it is difficult to make out whether Mr. Rahim, 26, who was under police surveillance at the time, was carrying a knife, as the officers have said.

It is possible to discern, however, that the law enforcement officers — five F.B.I. agents and one Boston police officer — backed away from Mr. Rahim at one point, a retreat that the authorities said indicated the officers felt threatened. Shortly after backing away, the officers closed in on Mr. Rahim, coming within three or four feet, before he fell to the ground. One of the officers then reached down to the ground and picked up an object that the authorities said was a large, military-style knife.