The man, who was not immediately identified, was wearing scuba equipment to carry out maintenance at a deep pool on a ranch near Palmdale, in the desert north of Los Angeles, where "The Lone Ranger" is being shot, a spokesman at the Palmdale Sheriff's station said.

It was not immediately clear how the man died.

"We regretfully confirm that a 'Lone Ranger' crew member has passed away after being taken to a local hospital. Our hearts and thoughts are with his family, friends, and colleagues at this time, and our full support is behind the investigation into the circumstances of this terrible event," Walt Disney Co studio spokesman Paul Roeder said in a statement.

The man was thought to be preparing a tank for an underwater scene to be shot at a later date, a source close to the production said. There was no filming underway on the set when the incident occurred. The source did not want to be named because the investigation is ongoing.

"The Lone Ranger", a new spin on the classic Western adventure with Depp as Native American spirit warrior Tonto and Armie Hammer in the title role, is due to be released in July 2013.

(Reporting By Jill Serjeant; editing by Carol Bishopric)

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