ERIE, Pa. - Crews say they quickly extinguished a fire at a shipyard in Erie, but have yet to determine its cause.

Erie Deputy Fire Chief Marty Heid tells the Erie Times-News that the fire started shortly before midnight Thursday in the engine of a crane used to lift workers. Nobody was using the crane when the fire started, though.

The fire occurred at DonJon Shipbuilding and Repair, but officials say all employees got out safely.

Heid says crews contained the fire to the crane and extinguished it in about 15 minutes, but not before a few oxygen tanks nearby exploded from the heat.

A fire investigator says he still didn't know Friday morning what caused the fire.

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Information from: Erie Times-News, http://www.goerie.com

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