Police received a call at 11:23 p.m. Wednesday reporting that a man at a home in the 5200 block of Balhan Court had shot himself, Concord police Cpl. James Carroll said.
Officers and medical personnel arrived and found the man, identified by the coroner's office as 21-year-old Cesar Martinez, suffering from a single gunshot wound to the head, Carroll said.
Medical personnel performed life-saving measures on Martinez and then transported him to John Muir Medical Center in Walnut Creek, Carroll said.
The incident is still under investigation, but initial reports suggested that Martinez was attending a gathering at the apartment when he apparently shot himself accidentally while handling the weapon, Carroll said.