No injuries were reported after a Green Line trolley rolled backward and “hitched” onto another trolley Wednesday, according to the MBTA.

The MBTA partially shut down service on the Green Line in Boston Wednesday night because a trolley rolled back into the trolley behind it at Park Street. Approximately 100 passengers were told to get off the trolleys and walk through the tunnels to reach an exit.

An MBTA Green Line trolley parked at the Park Street station collided with another trolley behind it Wednesday evening, NewsCenter 5 has learned.

Shortly before 7:30, a stopped Green Line trolley at Park Street rolled backward and hitched to the trolley behind it, officials said.