Police said one caller reported hearing seven or eight shots being fired in one of the theaters of the Sparks Century Theater Tuesday, a police report indicated.
Witnesses inside the theater said only one shot was fired when a patron was moving in his seat and his gun fell to the floor and accidentally discharged, the report said.
"The subject got up, apologized, and exited the theater prior to police arrival," the police report said. "The subject was later located at a hospital in Reno with a through-and through-gunshot wound to his buttocks."
The wound wasn't considered life-threatening.
Police said the man was cooperating with the investigation and admitted the gun fell out of his pocket and discharged when it hit the floor.
"There was no panic in the theater as only five people heard the shot out of the approximate 30 people in attendance," the report said.
The shooting incident in Nevada is one of several gun incidents at movie theaters since James E. Holmes, a former graduate student at the University of Colorado, allegedly killed 12 people and wounded 58 others July 20 during a midnight showing of "The Dark Knight Rises" in Aurora, Colo.