Two people were killed and nine others were injured Saturday in a massive pileup north of Los Angeles that involved as many as 40 vehicles in foggy conditions on Interstate 5, authorities said.
The deadly pileup on the West Coast's main north-south corridor occurred on the southbound side of I-5 in Kern County, about 33 miles north of the Los Angeles County line, according to the California Department of Transportation, known as Caltrans.
The freeway remained closed at Millux Road as California Highway Patrol investigators attempted to reconstruct elements of the pileup and determine an official cause, CHP spokesperson Tami Grimes said.
Grimes confirmed two fatalities. She said more details were expected Saturday night.
Kern County Fire Department Battalion Chief Jim Calhoun told NBC affiliate KGET of Bakersfield that nine other people were hospitalized with minor injuries.
Caltrans said foggy conditions affected the freeway Saturday morning, and Calhoun said visibility was down to about 10 feet when rescuers arrived.
Grimes said as many as 40 vehicles were involved in what appeared to be three core collisions in close proximity to one another. The battalion chief said 18 of the vehicles were tractor-trailers.
The pileup was reported shortly after 7:30 a.m., according to KGET. It happened along a rural stretch of the freeway in the town of Conner, north of a snow-prone area known as the Grapevine.
Such low-visibility conditions are known in the San Joaquin Valley as tule fog, which covers the ground in a heavy, rising mist after rain saturates the soil. KGET said the fog can linger as high-pressure air traps it.
The area was in for more hazardous weather Saturday night through Sunday as a southbound storm was forecast to deliver a few inches of snow to the Grapevine, the National Weather Service said.
Forecasters also warned that the corridor north of Los Angeles could be affected by ice and wind gusts as powerful as 80 mph.
Motorists should beware of "blizzard conditions with low visibilities from blowing snow," the weather service said.