Updated

A third body was recovered from a Southern California freeway tunnel fire Saturday evening, said Los Angeles County coroner investigator Kelly Yagerlener.

Two bodies were pulled out of the tunnel early Saturday morning after a 15-truck pile-up caused a massive fire, blocking a key link between Los Angeles and San Francisco.

Fire Inspector Jason Hurd said the accident — the wreckage stretching a half mile — began when two trucks collided late Friday and started a chain reaction in Interstate 5's southbound truck-only tunnels.

At one point flames shot out of the tunnel and 100 feet into the night sky, said Los Angeles County firefighter Scott Clark, one of some 300 firefighters battling the blaze at its height.

"It looked like a bomb went off," said Clark, who battled the flames throughout the night.

The charred skeletons of at least a half-dozen big rigs peeked out of the tunnel's south end. At least one truck was carrying produce, and a smoldering load of cabbages lay scattered across the pavement.

By mid-morning most of the flames appeared to have been extinguished, although thick columns of smoke were still curling out of the tunnel and into the surrounding canyons. Firefighters began pouring flame-retardant foam into one end of the tunnel to douse any hot spots.

Twenty people evacuated the fiery tunnel on foot, including the 10 injured, Hurd said, and five trucks were stuck inside. One truck driver was unaccounted for, and authorities were worried that more may be missing. Authorities also removed two bodies from the scene, but their identities are not yet known.

Although the tunnel is designed to carry truck traffic through a mountain pass area, Hurd said passenger cars may also use it, raising concerns that some may be trapped inside.

"We're going to have to do a very methodical search," Deputy Chief John Tripp told KABC-TV said. "There could be unfortunately more people that were not able to escape."

Authorities said eight had minor injuries and two had moderate injuries, ranging from moderate burns to neck and back injuries. All 10 injured were taken to local hospitals.

The intense heat caused concrete to crack and melt, sending chucks falling onto the road below throughout the night. Firefighters worried that the damage could cause parts of the tunnel to collapse.

"The tunnel may be structurally compromised, so we're fighting the fire from outside right now," Tripp said.

State transportation department engineers were inspecting the tunnel and the freeway above to determine whether firefighters and rescue workers could enter to douse the remaining flames and look for anyone who might have been trapped.

The interstate, a key route connecting Los Angeles to San Francisco, as well as a major commuter link connecting Los Angeles to its northern suburbs, was expected to remain closed throughout the day Saturday and perhaps longer.

"It could be another day, it could be days, it could be weeks," Hurd said.

The freeway is roughly 30 miles northwest of downtown Los Angeles.

The Associated Press contributed to this report.