Two workers were inside the truck when they saw the train approaching as they worked on the tracks in Newington. The workers were able to get out before the train struck the vehicle at around 11 a.m.
More than 60 people were on board the train, which was heading north from New Haven to Springfield, Massachusetts. Amtrak officials said six riders reported minor injuries.
The train was scheduled to arrive in Springfield around noon. Officials say passengers will be transferred to another train scheduled to arrive in Springfield after 1 p.m.
Police, fire and ambulance officials, meanwhile, are on-scene and Amtrak says the cause of the crash remains under investigation.