Human error caused New York City subway train derailment

A subway train derailment in New York City that injured nearly three dozen people and sparked major delays is being blamed on human error, not a track defect.
A preliminary investigation indicates the derailment in Harlem just before 10am on Tuesday was caused by "an improperly secured piece of replacement rail that was stored on the tracks", Metropolitan Transportation Authority (MTA) Chairman Joe Lhota and Interim Executive Director Ronnie Hakim said in a joint statement.