A man who police say walked into Stater Bros. carrying a shotgun was shot and killed by police Sunday night.

The shooting happened at about 10:44 pm at the grocery store on East 4th Street in Ontario, reports KTLA.

Police responded to calls from customers who said that a man had walked into the store with a shotgun. Officers entered the store and found the man was armed with a shotgun, then an officer involved shooting occurred.

The man, who has not been identified, died inside the store. No one else was injured.

Authorities told ABC 7, it is not clear at this point why the man took the weapon inside the store.

“Right now, we are in the beginning stages of trying to figure out who he was and what his actions were prior to coming into the store, as well as while he was inside of the store,”  Detective Melissa Ramirez of the Ontario PD told the TV station.