PITTSBURGH (AP) — Federal authorities have decided against issuing citations in a natural gas well fire in southwestern Pennsylvania that killed one worker earlier this year.

The federal Occupational Safety and Health Administration said no exact cause was determined for the Feb. 11 fire at the Chevron well in Greene County's Dunkard Township. No citations for violation of federal safety standards will be issued.

Twenty-seven-year-old worker Ian McKee was killed.

The state Department of Environmental Protection said in a report last week that the fire "may have been caused by human error" when a lock screw was ejected, allowing high-pressure methane gas to escape.

The state report said sufficient oversight was not always provided and a contract worker with no oil field experience worked on the well contrary to company policy.

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