The office said the 43-year-old woman drew the gun from a holster under her left arm with the intent to fire it at mice she had seen on the floor of a trailer that was traveling on Highway 20 in the town of Potter Valley, the Santa Rosa (Calif.) Press Democrat reported Thursday.

However, the woman dropped the gun and it fired a round when it struck the floor, the report said. The bullet went through the woman's kneecap, glanced off keys on the belt loop of a 42-year-old man who was also inside the trailer, tore a hole through the man's pants and grazed his groin before coming to a stop in his coin pocket.

The sheriff's office said the bullet has been admitted to evidence. The victims' names were not released.