A T motorman has been placed on administrative leave after the Red Line train he was operating left the Braintree station with no operator and kept going for 9 minutes, MassDot officials said today.

Passengers tell the Herald it was an unnerving morning commute that left the Braintree stop for what social media has dubbed a ghost ride.

"I got nervous with everything going on in the world. You think the worse. Then the lights started flickering. The power went out, and we coasted to a stop." said Geno Clemenzi from Duxbury. "There was no communication. The speakers are pretty rough shape. It was a bit unnerving."

Fernanda Daly, a clinical research technician, said it took her a while before she noticed something was wrong. "We pressed the intercom alarm that you can talk to the driver and nobody answered so I thought the driver went out,” she added.

State Transportation Secretary Stephanie Pollack said the investigation is focused on "operator error" after the train went unattended before the T cut the power.

"The MBTA's first and foremost responsibility to its riders is to make sure that we keep them safe. As I think everyone knows by now, this morning an incident occurred on the Red Line that represents an unacceptable breach of our responsibility to keep our riders safe," said Pollack at a press conference late today.

She said the train operator was unable to start the train at the Braintree station and was cleared by the MBTA Operations Control Center to undertake a bypass at 6:09 a.m. The operator exited the train to "undertake that procedure and while the operator was not on board the train left the station," she added.

The operator reported the runaway train to the MBTA official at Braintree and "there was an immediate response on the part of the operation response center," Pollack said.

The 50 passengers on the train at the time rode without a conductor until the train came to a stop out the North Quincy station. There were no reported injuries, Pollack said.

Braintree Mayor Joe Sullivan, who sits on the MassDOT board of directors, spoke this morning with T General Manager Frank DePaola and others about the incident, he told the Herald earlier today.

Sullivan said, "It looks like the driver manipulated the train in such a way that when he flipped the switch on the train, it took off. There was manual manipulation of this train."

"This is a case of human error; it is not a technological problem,” Sullivan said.

“This has not been a good week for the Red Line. We have some challenges operationally. We have been making several steps to prepare for this," Sullivan added. "This is another instance where we have to make sure — We need to review it, and we have to make sure we are ready with the coming months."

MBTA employees boarded the train after it was de-powered after reaching the North Quincy station, taking it to the JFK/UMass stop where the train was emptied of its passengers, according to MassDOT.

“Passenger safety is the highest priority for the MBTA and this highly troubling incident is under investigation by Transit Police detectives,” said MBTA general manager Frank DePaola in a press release.

Earlier in the day an MBTA spokesman confirmed a train operator for the transit agency had been injured after being brushed by a train in Braintree. The train operator suffered a minor injury, said MBTA spokesman Joe Pesaturo.

James O'Brien, president of the Boston Carmen's Union, said he believes the man was taken to South Shore hospital. Union officials are trying to reach out to him.

O'Brien said the union was withholding comment on the incident until the investigation is completed.

The operator of the train, who was not identified, is 51 years old and has been with the T for 28 and a half years, Pesaturo said.

Gov. Charlie Baker, speaking on Boston Herald Radio this morning, said the train was “tampered with,” but didn't elaborate, citing the ongoing investigation.

“They're currently interviewing several people, including the gentleman who was the operator,” Baker said, adding that nobody was hurt despite there being passengers on the train. “This train was tampered with and it was tampered with by somebody who knew what they were doing.”

Baker called it an “isolated” incident, though he agreed with a comment that the situation felt like it's “out of a movie.”

Baker, speaking early this afternoon at a separate event in Plymouth, reiterated that the “main control that drives the train” had been “manipulated.” He said within minutes of the train leaving Braintree Station, power was cut to the third rail, but the train coasted through several station because it already had momentum before stopping near the North Quincy station.

“It's pretty clear it was set in forward motion, which is why it moved in the first place,” Baker told reporters, adding that the operator stepped off the train to check a problem with the signal.

“He got out to check the signal, and then it went forward,” Baker said. “I think the big issue on this is whether this was a negligence issue or something else.”

Baker added that the FBI is not directly involved “at this point” in the investigation, which is being handled by the MBTA, MassDOT and the state's public safety office. The Federal Transit Administration also is investigation the incident, according to a Baker aide.

Were you on the MBTA runaway train? Email the Boston Herald at citydesk@bostonherald.com.

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