Smoke filled State Street station after a third rail issue caused severe delays on the Orange Line Tuesday night.
The MBTA reported delays and fire department activity on the Orange Line around 9 p.m.
T spokesman Joe Pesaturo said "a defect in the third rail caused to trains to go disabled," he said. There was no fire, he said.
At 9:47 p.m., one of the trains was still in the station, he said, adding that power had been restored to the system.
Reports on Twitter indicated that smoke poured into the station, and there were unconfirmed accounts of riders kicking out windows and a loud boom.