The police car and the train crashed at the Poole's Lane crossing in Rockport around 8 p.m. on Sunday, June 4, according to Rockport Police Chief John Horvath.
The officer who was in the police cruiser was injured and taken by ambulance to a local hospital for treatment.
The train's 10 passengers were uninjured.
Information was not immediately released about the logistics of the crash, but both the train and cruiser were traveling at a low rate of speed at the time of the incident.
The crash is under investigation by MBTA Transit Police.
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