An underground explosion rocked a portion of West Philadelphia late Tuesday and it appears that gas is to blame.



The blast happened under the street near 56th and Market just after 11 p.m. and was powerful enough to blow six manhole covers off, completely destroying three and damaging nearby cars.



The lastest information indicates that there was an accumulation of gas underground. A shorted traction feed cable used to service the Market-Frankford El and trolleys ignited the gas causing the explosion, according to SEPTA.



As a precaution, the Philadelphia Fire Department closed Market Street between 56th and 59th Streets.



That road has since been reopened.

