The MBTA says a westbound Green Line trolley car derailed as it entered Park Street Station just before 9 a.m.
No one was injured and the cause remains under investigation. There were more than 200 people aboard the train.
MBTA Green Line Train Derails
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As a result of the derailment, the Green Line experienced severe delays between North Station and Park Street.
Green Line service was temporarily suspended between Haymarket and Park Street Stations. Service resumed around 12:45 p.m., but the MBTA said some residual delays should still be expected.
Many Green Line riders took to Twitter to express their frustrations with the situation: