UPDATE: Transit Police report the man was taken out alive from under the train.
A man jumped in front of a train around 2:20 p.m. on the outbound side of the Red Line.
One witness on the platform said he heard a "boom" then screeching as the train driver hit the brakes.
The MBTA substituted bus service between JFK/UMass and Kendall as firefighters and paramedics worked to extract the man and get him to a hospital.
Firefighter with Jaws of Life going down to platform: