By CBSBoston.com Staff

BOSTON (CBS) — MBTA service on the Green Line resumed on Saturday morning, hours after a crash on Commonwealth Ave. injured 25 people. The collision happened shortly after 6 p.m. Friday on the B Branch near Boston University’s Agganis Arena.

One of the operators involved is on administrative leave, the MBTA announced Saturday afternoon. The employee has been with the agency for seven years. They were operating the first car of the two-car train that hit the other two-car train from behind.

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No other operators have been placed on leave.

Shuttle buses had been in place between Kenmore and Washington Street.

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The MBTA said this weekend’s scheduled construction on the B Branch was canceled.

Friday evening’s crash is still under investigation. MBTA General Manager Steve Poftak said the two trains were traveling westbound when the trailing train struck the one in front of it.

The MBTA said 25 people received medical attention after the crash. EMS workers from Boston and Brookline transported 23 people to hospitals, the driver of the rear train was among them. None of the injuries are life-threatening.

“Obviously at some point, they became too close together, that is a situation that should not happen,” Poftak said. “The investigation will dig into why that happened.”

The National Transportation Safety Board is also investigating.

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The Green Line Train Protection System is a $170 million project is designed to reduce the risk of train collisions by installing signal overrun protection, collision avoidance monitoring, and speed enforcing transponders. Installation of components in trains and along the tracks is anticipated to begin early next year and the project will be completed by 2024.

CBSBoston.com Staff