Authorities are investigating the apparent drowning of a crew member who was working on a set for 'The Lone Ranger' film.
Coroner's spokesman Ed Winter said a 48-year-old man was pronounced dead.
He was cleaning a pool that was going to be used in the film in Acton, which is in north east Los Angeles County. Mr Winter said it appears the man suffered a heart attack.
The man's identity was not released.
Walt Disney Studios is producing the film starring Johnny Depp.
It expressed its condolences, saying the studio's thoughts are with the man's family, friend and co-workers.
The studio is also co-operating with the investigation, which will include a post mortem to determine his cause of death.