An MBTA spokesman said police are still investigating how the person came to be on the tracks before being hit by an inbound train shortly before 4 p.m..
Shortly after 4 p.m., a rider on one train e-mailed UHub:
Train stopped due to what the conductor said is an apparent suicide between the two stops. He said the police are going to be on the scene for a few hours, so now we're waiting for the train to turn back to West Concord to disembark the train.
Transit Police report the man was between 20 and 25. The investigation shut the tracks and caused lengthy delays in both directions.