NEW YORK (AP) — A subway train that derailed Tuesday as it entered a station, tossing people to the floor and forcing hundreds of shaken-up passengers to evacuate through darkened tunnels was caused by an "improperly secured piece of replacement rail" that was stored on the tracks, New York City transit officials said.Nearly three dozen people suffered minor injuries in the derailment, which happened in Harlem just before 10 a.m."Storing equipment in between [...]