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SHIPPINGPORT, Pa. (AP) – Authorities say two contractors who inhaled toxic fumes at a Pennsylvania power plant that killed two other workers have been released from the hospital.

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Another worker remains hospitalized but is improving.

Enerfab Corp. chief executive officer Scott Anderson says the employees were discharged from the hospital Friday. He says a 43-year-old worker still hospitalized “continues to show signs of improvement.”

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Police said the contractors were in a “confined, well-type” area at the Bruce Mansfield Power Station in Beaver County when hydrogen sulfide gas was released early Wednesday. Police said 34-year-old Kevin Bachner and 42-year-old John Gorchock, both of Pittsburgh, were unable to make it out of the well and died.

The accident at FirstEnergy’s largest coal-fired plant in Shippingport, about 35 miles northwest of Pittsburgh, remains under investigation.

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