As officers climbed the stairs to arrest him, he allegedly yelled,"I'm going to shoot you" and pointed a black handgun in an officer's face.

Costa yelled "gun" to alert the other officers and stumbled backwards, pushing another officer down the stairs, police said. Mammano

continued to point the gun at officers and threaten their lives, police said. Captain John O'Connor fired his weapon one time, police said, before Mamano threw his gun down the stairs and was apprehended.

Mammano allegedly punched and kicked officers as they tried to arrest him.

He was arrested and charged with threatening to commit a crime, resisting arrest, assault with a dangerous weapon and assault and battery on a police officer.