A Boston subway train caught fire on a bridge Thursday morning, causing chaos as commuters escaped through windows and one straphanger resorted to jumping into the river below.

Wild video taken from inside the train showed passengers climbing through windows of the train and fleeing onto the tracks. Footage from the tracks also shows passengers-turned-good Samaritans catching one another as they jumped out the windows with smoke billowing around them.

“An unidentified female passenger jumped off the bridge into the river,” Somerville Fire Chief Charles Breen told the Boston Globe. “Our marine boat happened to be in the river for training and was on scene immediately.

“The woman refused to get into the boat. She was provided a life jacket and proceeded to swim to shore … then she walked away,” Breen added.

The Orange Line train on Boston’s MBTA system was traveling over the Mystic River when it burst into flames just before 7 a.m., the Globe reported.

Local authorities said 200 passengers evacuated the train, which was headed toward a Somerville, Massachusetts, station. There have been no reported injuries or deaths.

“Welp, got my morning walk in I guess,” a Twitter user named PJ posted along with a video of himself and others walking along the Orange Line tracks after fleeing the burning train. 

“The train stopped and sparks starting coming out of the front, probably about three feet behind the driver,” witness John Gosselin told Boston 25 News.

Gosselin was staying in a nearby hotel and had a view of the bridge from his room. “I saw a flame and then I knew something was up…It engulfed very, very quickly. The flames were shooting up. The smoke got very black,” he added.

The MBTA said regular service resumed on the Orange Line by 10:30 a.m. and cited “mechanical problems.” The cause of the fire has not been revealed.