Passengers reported seeing smoke on a Red Line train at Andrew Station on Tuesday afternoon.
The MBTA said on Twitter that there was a mechanical problem on a train at Andrew Station and that northbound Red Line trains might experience "a gap in service." Regularly scheduled service resumed shortly before 3:30 p.m.
The smoke was caused by a blown motor, the MBTA said. Ventilation fans were enabled and the tracks were inspected. The train was removed from service and sent back to the yard.
Twitter reports from passengers started coming in shortly before 3 p.m.
"Two huge electrical arcs just shook Andrew station like explosions," said Greg Simoneau. "The whole station just lit up like it was struck by lightning. We can now smell something burning and smoke everywhere." He later added that he saw fire.
Another passenger posted video to Twitter showing people exiting the train and smoke in the station.
The incident comes a day after Massachusetts Gov. Charlie Baker rode the Red Line to a tour of the renovated Wollaston Station.
No further information was immediately available.