A Caltrain slammed into a vehicle working on the transit system's electrification project in San Bruno Thursday morning, sparking a fire and leaving at least 13 people hurt, according to the transit agency.
A Caltrain engineer and an equipment operator were among the injured, Caltrain spokesman Dan Lieberman said. The other 11 people hurt were believed to be passengers. None of the injuries were considered to be life-threatening, but six people were transported to the hospital.
"This is a rough day, but the fact that none of the injuries appear to be life-threatening is a bit of good news," Lieberman said.
Southbound train No. 506 struck the vehicle – a truck with a crane attached – at about 10:38 a.m. near Scott Street, Lieberman said.
Footage from the scene showed the mangled truck engulfed in flames as well as a trail of flames on the tracks beneath the train.
Passengers evacuated the train as flames reportedly reached the passenger cars.
"We tried to open the exit," passenger Kyle Ha said. "We were trying to take the hammer and open it. It took a while."
There were approximately 75 passengers on the train at the time of the collision, according to Lieberman.
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Lieberman said removing the train will "take some time" due to damage to the tracks that needs to be repaired.
Caltrain and other agencies are trying to figure out why the collision happened.
The crew with the crane was working on Caltrain's ongoing effort to switch to electric-powered engines. There is supposed to be a system that tracks train traffic, but somehow that failed.
"We've been doing this construction work since 2017 without an incident like this, so it is not clear what went wrong," Lieberman said.
Caltrain said work on its electrification project has been temporarily suspended "to ensure that all appropriate safety protocols are in place before electrification work recommences."
Fire crews were also trying to figure out if other vehicles were struck by the train.
"There's potentially one other vehicle that's involved in the accident," San Bruno Fire Department Chief Ari Delay said. "It's potentially underneath the train between the train and this other vehicle."
How is Caltrain service impacted?
Caltrain said riders should expect to face major delays due to the collision.
Service was being turned south at Millbrae.
BART was offering mutual aid for Caltrain riders from Millbrae to Embarcadero in both directions.
SamTrans was also offering mutual aid for Caltrain passengers travelling from Millbrae north to San Bruno, South San Francisco and San Francisco. Passengers should use Route ECR or 398 from Millbrae northbound. Additional details can be found at samtrans.com.
Caltrain riders are instructed to follow Caltrain Alerts on Twitter for real-time updates.
Watch aerial video showing aftermath of fiery crash involving Caltrain
The video below from NBC Bay Area SkyRanger shows the aftermath of the collision between a Caltrain and truck with a crane.