From the Associated Press:

Investigators methodically picked through scorched tire rims, truck axles and other wreckage Sunday looking for the cause of a fiery Interstate tunnel crash that killed three, while commuters braced for a likely traffic nightmare at the start of the work week.

With Interstate 5 shut down in both directions around the crash site, traffic was strangled on surrounding roads where drivers looked for alternative routes following the tunnel pileup Friday night. The southbound lanes were closed for two-and-a-half miles; the northbound side was closed for about a mile.

Gov. Arnold Schwarzenegger declared a state of emergency in Los Angeles County, which will allow the state to deploy emergency personnel and provide assistance to local government under the California Disaster Assistance Act.

California Highway Patrol Assistant Chief Warren Stanley refused to speculate on the cause of the crash, but said authorities would finish their on-scene investigation Sunday. He did not know when findings would be released.

Investigators determined that 28 commercial vehicles — including big rigs — and one passenger vehicle were involved in the crash that killed two men and an infant and injured at least 10 people, Los Angeles County Deputy Fire Chief John Tripp said.

The fire spread from vehicle to vehicle, sent flames shooting nearly 100 feet in the air outside the tunnel and reached temperatures as high as 1,400 degrees.

The chief said it was remarkable 10 people were able to escape on their own, given the extent of the crash and the intensity of the blaze, which was fueled for hours by truck cargo.

"When we look at tunnel fires ... it's pretty miraculous those people were able to get out," Tripp said.

The fire "consumed everything that was burnable" and left only "molten metal, frames of vehicles," Tripp added.