FONTANA, Calif. (AP) — Southern California authorities are searching for a mountain lion that killed a family pet in the backyard of a foothills home.

A Fontana police statement says the lion displayed aggressive behavior toward a resident who heard his dog in distress at 3:30 a.m. Wednesday and found the cougar standing over the dead German shepherd.

Arriving police officers found the lion in the home's front yard and fired at it, scaring it into a canyon. The lion returned and moved toward the officers four times before retreating to the canyon. Police say there's no evidence it was struck by the gunfire.

Fontana police deemed the lion a threat to public safety and are assisting state Fish and Wildlife officers in searching for it, including using a helicopter equipped with heat-seeking equipment.