LOS ANGELES (AP) — Authorities are investigating the apparent drowning of a crew member who was working on a set for upcoming "The Lone Ranger" film.

Coroner's spokesman Ed Winter says a 48-year-old man was pronounced dead around 10 a.m. Friday. He was cleaning a pool that was going to be used in the film in Acton, which is in northeast Los Angeles County. Winter says 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 cooperating with the investigation, which will include an autopsy to determine his cause of death.