A man was shot and killed by police after he allegedly threatened residents and staff of a suburban assisted living facility with a chainsaw on Sunday.

A man who Illinois authorities said threatened senior-living facility residents and staff with a chainsaw on Sunday was shot to death by police.

A man wielding a chainsaw inside a senior-living facility in St. Charles, Illinois, was shot and killed by police early Sunday, state and local law enforcement said. "Just before police arrival, witnesses advised the subject had now gained entry to the lobby of the building and began confronting residents with the chainsaw,

The man, who did not have authorization to be in the Illinois facility, confronted residents while armed with the chainsaw, police said.

A use-of-force investigation is underway in the fatal police shooting of a chainsaw-wielding man who threatened residents of a St. Charles assisted living center Sunday morning. Authorities have not yet released the suspect’s identity,

ST. CHARLES, Ill. (CBS) -- Police in St. Charles shot and killed a man they said was trying to attack officers and residents of a seniors' assisted living center with a chainsaw Sunday morning.

A man who was shot and killed while wielding a chainsaw inside an assisted living facility in a Chicago suburb has been identified by police.

A chainsaw-wielding man was shot and killed by police at a senior living facility near Chicago Sunday. Police said it started after they got a call about a shirtless man trying to cut down a tree with a chainsaw at the River Glen of St. Charles senior living center, according to ABC 7 Chicago.