Authorities say a 19-year-old Portland man’s leg was severed when he was struck by a train. Police say it appears the man was trying to hop onto the freight train in the city at about 6:30 p.m. Sunday when he fell off and his leg was severed. Residents of nearby homes heard the man’s cries for help and called police. The first officer on the scene applied a tourniquet which Lt. Gary Hutcheson says likely saved the man’s life. He was taken to Maine Medical Center and is expected to survive. His name was not immediately made public. The Boston and Maine Railroad Police are investigating, but police noted that walking along the tracks is considered trespassing.