SAN BRUNO (CBS SF) -- A Caltrain engine slammed into a construction vehicle, ripping it in half and igniting its fuel tank into a massive fireball Thursday morning in a crash that injured 13 people, charred the outside of several passenger cars and shut down service on the busy San Francisco Peninsula commuter rail line.
Fortunately, transit officials said, all the passengers aboard southbound Train 506 escaped injury. There were 75 people on the train at the time of the collision, officials said.
The collision near Scott Street in San Bruno happened around 10:38 a.m. when the train collided with "on-track electrification equipment" being operated by a contractor. Caltrain officials confirmed the driver of the vehicle was transported to the hospital. San Bruno Fire officials later said that the driver suffered from burns on his extremities.
Officials later said that there were actually two pieces of on-track equipment involved in the collision, one of them being a crane.
Two Caltrain workers who were in the operator's compartment at the front of the train were also injured, but their injuries were non-life-threatening, according to officials.
A Caltrain spokesperson later confirmed that a total 13 people were injured in the collision, but none of the injuries appeared to be life threatening. San Bruno Fire officials said that five of those injured individuals were transported to area hospitals.
The force of the impact ripped the construction truck apart, with the burning cab remaining in front of the engine and another large piece of wreckage coming to rest several cars back. Burning gasoline could be seen under several cars.
Fire crews could be seen in video from Chopper 5 dousing flames inside at least one passenger car at the scene not far from the San Francisco International Airport. Caltrain said there was smoke in the passenger cars as the train was evacuated.
Video from Chopper 5 also showed a triage area that was set up near the damaged train cars with emergency first responders on the scene.
The San Bruno Fire Department confirmed that they responded with 25 units and a total of 60 personnel.
"The train conductor was able to work to evacuate the train," said San Bruno Fire Chief Ari Delay. "That was critical in the success to make sure nobody lost their life today."
Twitter user Jesse Miller posted photos and video that showed the aftermath from the collision with a large fire burning where the train struck the vehicle.
"Craziest #Caltrain ride ever. I think everyone got off the train safely," he tweeted.
Video he posted showed fire on the tracks where the train appeared to have dragged the vehicle, likely burning gasoline leaking from the demolished truck.
He later spoke with KPIX about the harrowing experience.
"It was pretty chaotic. There was maybe 15 seconds where nobody knew what to do," Miller told KPIX. "Some people started opening up the emergency exits in the windows. Some people actually jumped out of the windows."
"I saw one worker who was taken away in an ambulance. He looked like he got some cuts and serious bruises," said Caltrain passenger Elizabeth Tom. "I saw another passenger, he had a gash on his eye."
The Brisbane Fire Department provided support during the incident, and firefighters with the department posted several photos on Instagram showing the extent to the damage the interior of the Caltrain cars. The post noted that the firefighters were part of a two-alarm response and that two of the Caltrain cars were involved in the fire.
One photo showed the inside of one train car that was heavily fire damaged with smoke still filling the car.
Caltrain officials said the incident is currently under investigation to determine the cause.
"All the equipment should have been cleared of the tracks when trains come through," said Caltrain spokesperson Dan Lieberman. "We've been doing construction on the tracks throughout electrification. That's under investigation."
Additional agencies including the NTSB are also investigating the incident.
Lieberman said Caltrain hasn't had any incident like this happen in the past. There are many questions they need to answer.
"There are watchmen on site that are communicating with dispatch, but ultimately, it's not clear where the breakdown took place," he said. "This is not exactly a happy day, but we're glad it is not worse than it is."
"Our deepest thoughts and sympathies are with all those who were injured today," said Caltrain's acting executive director Michelle Bouchard in a statement issued by the agency. "Caltrain's core values have always prioritized the safety of our passengers, employees and the communities we serve, and we are deeply disappointed that those standards were not met today. We have a long history of providing safe and reliable service and we are committed to working closely with the NTSB and other regulators to determine the cause of today's incident. We will restore full Caltrain service as quickly and safely as possible."
Work on the system's electrification project has been temporarily suspended to ensure that all appropriate safety protocols are in place before electrification work resumes.
Passengers and neighbors who live near the crash site are eager to learn how this happened.
"These guys are working on this whole line every day," said area resident Larry Valencia. "I know they're super safety conscious and all of that, but why was that train flying on that track where the truck was?"
A bus bridge, operated by Caltrain to replace train service in the affected area, is in effect until at least 4 p.m. Friday between the South San Francisco and Millbrae Caltrain stations. SamTrans and BART wer also providing mutual aid.
For the rest of the system, Caltrain will continue to operate under its regular weekday schedule. Passengers traveling between the South San Francisco and Millbrae train stations should expect service delays as a result of the bus-bridge. Passengers can also find other public transportation options by visiting 511.org.
Max Darrow contributed to this story.
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