The fire in Somerville, north of Boston, was caused when a metal strip similar to aluminum siding came off a train car and came into contact with the third rail, which was carrying electricity, said Steve Poftak, general manager of Massachusetts Bay Transportation. . The authority said at a press conference. Mr Poftak apologized to 200 passengers aboard the Orange Line train, which had started the day at Forest Hills and caught fire between Wellington and Assembly stations around 6.45am. He called the fire “a terrifying incident and not the type of service we want to provide to our customers.” No one was injured in the incident and power was cut on the third rail less than two minutes after authorities received a call about it, he said. The woman who jumped into the river refused medical attention, the MBTA said. “This particular location is really an acute vulnerability,” Mr Poftak said. “You are a considerable distance from one of the stations and you are over there on the bridge.” The fire was the latest in a series of troubling incidents for the greater Boston area’s transit system, known as the T. Leaders are calling for more investment in the public transit system. Boston Mayor Michelle Wu called the latest episode on the Orange Line “more evidence of an aging transit system in crisis.” It was not immediately clear why the metal strip, which is attached to the train, slipped, Mr Poftak said at the news conference. He added that the current heat wave has “obviously” had an impact on the agency’s recent activities, saying officials struggled to get bridges to stick upright on Wednesday. He did not know if heat played a role in the train fire. “I don’t want to speculate,” he said. “It’s going to be something we’ll see.” Passengers climbed out of four large windows that had been opened on the train, and train crew members helped others off. An MBTA spokesman said in an email that the “vast majority” of passengers exited the rear door of the last car of the train, and that it was not immediately clear how the woman who jumped into the river left the train. He referred questions about the episode to the U.S. Coast Guard, which did not immediately return an email. Mr Poftak said service was restored at 11am after the inspections were completed. The train, which entered service in 1980, was last inspected on June 23 and the missing seal was inspected then, he said. Mr. Poftak said the MBTA and public transit in general was much safer than most other forms of transportation, but acknowledged that the system recently “has had a number of incidents.” In April, a man was dragged to his death after his hand got caught in the door of a Red Line train he was exiting, according to the National Transportation Safety Board. Last July, 20 people were injured when two Green Line trains collided, and in January 2021, a collision involving an MBTA rail bus and a vehicle killed the car’s driver, according to Bloomberg. “A broken MBTA threatens the safety of our community and the future of our city and region,” Ms. Wu, the mayor, said in her statement. “I will be reaching out to my colleagues across the region to work more aggressively with the state on rapid system-wide upgrades. The City of Boston must do more to help the state lead this transformation, and we are ready to prioritize this work.”