Three Metro employees were disciplined after an incident in which a 10-car train left the Shady Grove yard in a December, transit officials said..

Dan Stessel, Metro’s chief spokesman, said the three employees included one who was a terminal supervisor, one train operator and one interlocking operator, who is in control of allowing trains out of the rail yard.

He would not say which employee received what discipline but said it ranged from unpaid suspensions to “disqualifications from certain positions.” All three received “strong disciplinary action,” he said.

The incident occurred around 2 p.m. Dec. 2, when a 10-car train left the Shady Grove yard. Trains are meant to carry a maximum eight rail cars.

With a 10-car train, two cars were off the platform when it stopped at each station. The 10-car train managed to service 26 stations along the Red Line. No passengers were in the last two cars, Metro said.

Metro’s safety officials plan to update the board at its Thursday committee meeting.

Stessel said employee injuries are down because “we’ve been focused on employee safety.”

“We’re tightening up processes and awareness among employees,” he said. He said most of the incidents involving employees are the “result of inattention or working quickly or not wearing proper safety gear.”

Injuries to customers are up because of 10 bus collisions in the last year. One accident in December involved a pick-up truck that collided with the front end of a northbound Metrobus.

The bus driver was one of two people seriously injured in the accident. A total of eight people aboard the bus were taken to hospitals. The truck driver was killed.

Stessel said Metro has seen a decrease in incidents of bus operators using cell phones while driving — in part, he said, because the agency has a zero- tolerance policy for anyone caught texting or talking while operating a bus.

Metro has 27 “open and acceptable” recommendations with the National Transportation Safety Board. Of those, 15 are related to the fatal 2009 Red Line crash.

The Federal Transit Administration closed all of its recommendations on Metro, saying it believed the agency was “re-building a strong foundation to improved safety performance.”

At its Thursday meeting, Metro’s board will also decide what to place on the public docket for upcoming hearings on the budget for fiscal 2013. Metro General Manager Richard Sarles has proposed more money from local jurisdictions and a fare hike to help close a $116 million budget gap.

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