CHARLESTON, W.Va. (AP) -- The West Virginia Department of Environmental Protection has issued a notice of violation to Colorado-based Antero Resources for a drilling rig fire that injured three workers.

The DEP's Office of Oil and Gas said Thursday the penalty for the violation remains under review.

Antero was cited for failure to maintain well control at its Southern pad near Sycamore.

Last week, a spark ignited methane gas several hundred feet underground, triggering an hour-long fire on the floor of the natural gas drilling rig at Antero's Cottrill No. 3 well.

The victims worked for the contractor, Hall Drilling of Ellenboro.

The DEP has ordered Antero to cease any operations that aren't related to regaining control of the well. It also issued sampling orders for water wells within 2,000 feet of the site.

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