From TMZ:
Sources connected to the production tell us ... the man was working on a "condor" -- a high-powered lift -- when the machine tipped over and the man sustained fatal injuries.
Paramount released a statement saying, "Our thoughts and deepest condolences are with the [crew member's] family at this time."
The statement continues, "The safety of our cast and crew is our top priority and the studio is fully cooperating with all investigating agencies as they examine the circumstances surrounding this unusual accident."
In October, Nu Image/Millenium Films confirmed that one stunt man died and another was injured while filming an explosion scene for The Expendables 2. Earlier this summer an Avengers stunt performer was injured during a 30 ft. fall, suffering injury to his head. And in May, two crew members on The Hobbit were caught in a workshop explosion with minor injuries.
• 'G.I. JOE' SEQUEL Crew Member Dies After Accident On Set [TMZ]