Authorities say a ski-mask-wearing man who broke into his former girlfriend's house and threatened her with a gun was shot dead by their teenage son.

The Pinellas County Sheriff's Office said in a news release that early Tuesday morning, 46-year-old John Heisler broke into the St. Petersburg home where the girlfriend, the teen and the teen's younger sister lived. Authorities say when Heisler grabbed the woman, the new boyfriend called out for help, and the 18-year-old son emerged from his bedroom with a gun. The teen told police he shot his father after Heisling pointed the gun at him and his mother.

Heisler was pronounced dead at the scene. No charges have been filed.

Authorities say the boy's mother had obtained a temporary restraining order against Heisler in April.