A person working on the show "NCIS" died today after a man driving a passenger van for the production lost control and smashed into the set this morning ... TMZ has learned.



Law enforcement sources confirm ... the 60-year-old driver had some kind of medical emergency behind the wheel and veered on to the L.A. area set -- striking a 52-year-old male security guard.

We're told the security guard was transported to a nearby hospital in critical condition -- but died from his injuries a short time later.

The accident is still under investigation.

http://www.tmz.com/2011/02/09/death-died-dies-accident-ncis-cbs-security-guard-crash-stroke/