Flames and smoke were seen on a car of “a southbound Orange Line train approaching Assembly Station,” in Somerville, the Massachusetts Bay Transportation Authority (MBTA) said in a statement to CNN.
“Assisted by MBTA personnel, approximately 200 passengers were walked off the train, but some people did evacuate through windows in the first car,” MBTA added.
At least one person escaped by jumping into the Mystic River, according to CNN affiliate WFXT. That person was eventually rescued and “declined” medical treatment, MBTA said.
The train fire was caused by a piece of metal that runs along the base of the train coming loose, MBTA General Manager Steve Poftak said in a news conference.
The metal piece came loose and “made contact” with the third rail, resulting in sparking, smoke, and ultimately fire, Poftak added.
“Obviously this is a frightening incident, and not the type of service that we want to provide to our customers.”
No injuries were reported, and the MBTA said these are “initial” findings and they’re still investigating the incident.
Jennifer Thomson-Sullivan, who was in the train’s first car, told CNN that the train was approaching the Dana Bridge when she heard an explosion and the train immediately stopped.
“Everyone was jumping and screaming. You could smell burning and there was some smoke and then there were more explosions. At that moment, I truly thought I was going to die,” Thomson-Sullivan said.
Thomson-Sullivan said multiple people ran to the emergency door and tried to help a man trying to open it, but were unsuccessful.
“Once he gives up on that, he turns to the window and he starts kicking it and he finally breaks it and people just start flooding out the window,” she said.
Thomson-Sullivan said she almost followed the crowd out the window but decided against it when she saw she would have to jump several feet and realized the third rail was probably still active.
“I paused and then I realized the third rail was right there and I’m watching people pouring out of the window, so I start screaming, ‘watch the third rail!'” she said.
The conductor began telling people to get back on the train, and eventually, he and another person were able to get the emergency door open and lead passengers to the back of the train until the fire department showed up, according to Thomson-Sullivan.
She also added that one person jumped off the bridge and tried to swim to shore.
“I heard people scream ‘no, no, don’t do it,’ and then I turned around and saw someone in the water trying to swim to shore,” she said.
MBTA said that the Federal Transit Administration (FTA) and the National Transportation Safety Board (NTSB) have been alerted to the incident.
“I know that this must have been a terrifying experience. My heart goes out to those impacted by the fire today,” Massachusetts Attorney General Maura Healey said on Twitter. “Our residents should be able to depend on a safe, reliable public transportation system. It’s imperative that the MBTA rapidly address these persistent safety issues.”
Poftak apologized to those who were on the train as well as those who were indirectly inconvenienced by the incident.
Meanwhile, residents in the area can use bus shuttles operating between Oak Grove and Community College, MBTA said.