Investigators said it happened Wednesday at a home on U.S. 60 West in Olive Hill.
Troopers said they were assisting the Carter County Sheriff’s Office on a domestic violence call.
According to state police, authorities saw a man with a gun, assaulting a woman, inside the home.
State police said the man fired his handgun through a window where officers had been standing.
Investigators said the trooper then fired back, killing the man.
As of this writing, names had not been released.