BOSTON (CBS) – Federal investigators will meet Friday with representatives of the MBTA a day after a Red Line train left Braintree Station without an operator.

The Federal Transit Administration is sending an investigator to Boston on Friday to look into the Thursday incident along with the Massachusetts Department of Public Utilities and the State Safety Oversight Agency for the MBTA.

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MBTA employee David Vazquez. (WBZ-TV)

MBTA employee David Vazquez. (WBZ-TV)

On Thursday morning, transit officials said train operator David Vazquez, who has worked with the MBTA for more than 25 years, got off the train when he was unable to start it. Vazquez was given permission to put the train in bypass mode.

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Transportation Secretary Stephanie Pollack said a full-service brake and a hand brake must be engaged before a train goes into bypass mode, and it’s unclear if Vazquez followed that procedure.

Vazquez has been placed on administrative leave following the incident.

There were about 50 passengers on board the Red Line train, but none were injured.

Because of its momentum, the train traveled through four stations before coming to a stop just past North Quincy Station when crews powered down the third rail.

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In total, the train traveled without an operator for about nine minutes.