An underground fire that caused commuting problems Tuesday morning has been ruled accidental, reports New York WABC (http://7ny.tv/1u2Wszs)
The fire marshal reports the cause was electrical in area of temporary wiring used for lighting construction sites.
The third-alarm fire under Penn Station in Midtown started in construction sheds two floors beneath Eighth Avenue and West 33rd Street. It broke out just after 2:30 a.m., but Penn Station remained open. The construction area is under the West End Concourse.
The fire raged out of control for more than an hour, as 150 firefighters struggled to put it out, two stories beneath the street.
Heavy smoke filled the subway station on the A, C and E subway lines. A and E subway trains bypassed the 34th Street station for a period, and the subway station was evacuated of all MTA employees.