BILLINGS, Mont. — Authorities have identified a man killed by a Montana police officer after allegedly threatening patrons at a casino with a pellet gun thought to be a semi-automatic pistol.

The Yellowstone County coroner's office said Wednesday that 44-year-old Shawn Michael Hubbard of Billings was killed by two gunshot wounds to the chest.

Authorities say Hubbard was involved in a domestic disturbance with his wife early Tuesday morning before going to the nearby casino.

Police broke a window to get inside. Hubbard was shot by an officer who reportedly believed the pellet gun was a firearm.

It was Billings' second fatal police shooting in two days.

Corrections Department records show Hubbard had prior convictions for theft and fraudulently obtaining drugs in Lewis and Clark County. His sentence expired last year.