Melvin Sylvester kept moving toward him, with the knife raised, and the detective fired one shot into his chest, the official said.

The detectives at the turn could not fire; for their comrade was toward them.

A detective in the Bronx, trapped by a gang of black youths, had fired and wounded one.

Then the detective raised his gun and fired.

The detective fired a single round from his 9-millimeter Glock handgun, a police official said.

In the Grand Avenue apartment, the police said the detectives fired after at least one man went for his gun.

The detective fired, the barest fraction of a second too late.

The detective fired instinctively, even though Tocson's arm was dropping.

The detectives repeated the order, and then fired again, the police said.

The detective had fired the first shot as a warning.