According to Eng, MBTA employees are on leave pending the Cabot Yard investigation

He also did not provide a timeline for when the investigation would begin or what prompted the T to consider the allegations. The facility is located on Dorchester Avenue in South Boston and is used to store and maintain Red Line vehicles. It is also the home base for Red Line track workers and inspectors.

“As public servants, we have an obligation to fulfill the duties we have assumed in the roles,” Eng said. “These employees obviously didn’t do that.”

The investigation represents the latest controversy for the T, an agency reviled for slow trains, derailments, equipment malfunctions and allegations of employee negligence. When Eng took the helm in April 2023, the agency was enduring a long list of safety problems, such as the death of a passenger who was dragged by a Red Line train and a falling ceiling panel that nearly hit a commuter.

The new allegations come as federal regulators have been reviewing work and safety practices at the T. On Oct. 1, a Green Line train derailed in Cambridge, in part because the operator exceeded the posted speed limit, a preliminary report said. Less than two weeks later, a man suffered fatal injuries when he was struck by the driver of an MBTA bus at the Forest Hills station in Jamaica Plain.

Brian Kane, executive director of the T Advisory Board, said if the alleged conduct was true, it amounted to corruption and fraud. “The fact that people are abusing the public’s trust and misusing citizens’ fair and taxable funds to use public funds for their personal cars is annoying and frustrating,” he said.

While Kane praised management for taking disciplinary action, he said he wished the alleged scheme had been exposed sooner and that he would like to see “more of it” rooted out. “Who knows how long this has been going on?” he said.

During the T’s board meeting Thursday, Eng said reforming an agency’s culture is “probably the hardest thing” “because it takes longer.” Empowering staff to “speak up” when they believe change is needed is crucial, he said.

“Let’s show how we support each other, have each other’s backs and know that this is what we have to do, whether it’s a safety matter or a procedural matter, and that it’s important that we do that really do,” Eng said. “Nobody can do that. It takes the entire team from top to bottom.”

The T’s human resources department and labor relations team have begun investigating, Eng said. Then the transit police took over.

Eng’s comments following Thursday’s meeting marked the first time he publicly confirmed what the investigation was focused on. On Saturday, the T said it had placed employees at a T facility on leave pending an investigation, but did not provide details.

“We want to investigate this comprehensively. We know how important this is not only to what we want to do, but also to the public’s trust,” Eng said.

Thomas Glynn, the outgoing chairman of the T board, confirmed that the Cabot Yard situation was the subject of discussion during a closed board meeting Thursday. He declined to comment on what he learned, saying it would be “inappropriate.”

MBTA police did not respond to multiple requests for comment. Multiple messages left with the Boston Carmen’s Union were not returned this week. A union representative declined to comment before hanging up.

Several T employees who walked into Cabot Yard this week also declined to comment, saying they were not allowed to speak to the news media.

The T faces a funding gap in its operating budget that could balloon to more than $700 million next summer. Kane, a member of a transportation task force formed by Gov. Maura Healey, said this latest revelation makes it harder for advocates and lawmakers to push for more resources.

“When the public hears that this kind of corruption is taking place, it sticks in people’s minds,” he said. “It’s not the positive things that the T brings to our economy and our lifestyle.”

Shannon Larson can be reached at shannon.larson@globe.com. Follow her @shannonlarson98. Sean Cotter can be reached at sean.cotter@globe.com. Follow him @cotterreporter. Danny McDonald can be reached at daniel.mcdonald@globe.com. Follow him @Danny__McDonald.