LOS ANGELES (AP) -- A commuter van from NASA's Jet Propulsion Laboratory tumbled 200 feet off a twisting mountain road Wednesday, killing at least three people, authorities said.

The van carrying 11 people, including a driver, plunged off Angeles Crest Highway in the Angeles National Forest at about 6:30 a.m. and rolled down the mountainside, Los Angeles County Fire Department inspector Ron Haralson said.

"One person was able to get out of the van and make his way up to the road'' to get help, Haralson said.

Fire inspectors initially said four people had died in the crash, but they lowered the death toll during the rescue operation. Those three were pronounced dead at the scene.

Televised reports showed a badly battered white van lying in the middle of dense forest.

Firefighters tore off the doors to reach victims, who were lifted by helicopter to hospitals. Haralson had no details on injuries except to say some were serious.

Clouds and fog shrouded the site, at an altitude of about 1,500 feet. It wasn't immediately known if the fog had anything to do with the accident, which happened on a twisting, two-lane blacktop with steep drops.

The commuter van was from the Jet Propulsion Laboratory in Pasadena, lab spokesman D.C. Agle said. JPL is the control center for several NASA projects, including the Mars rovers.

The road is traveled by hundreds of cars daily. People living in the Antelope Valley area of the high desert northeast of Los Angeles use it as a shortcut to reach a freeway in Pasadena, said Terrie Trippel, a spokeswoman for the Angeles National Forest.