McALESTER, Okla. (AP) -- A second wrongful death lawsuit has been filed over a natural gas rig explosion in Oklahoma that killed five men -- three from Oklahoma, one from Texas and one from Colorado.

The lawsuit by Betty Jo Cunningham, widow of Roger Cunningham of Seminole was filed Friday, a week after the widow of Parker Waldridge of Crescent filed a similar lawsuit. Each names Red Mountain Energy and Red Mountain Operating, both of Oklahoma City, and Patterson-UTI Drilling and Patterson-UTI Energy, both of Houston.

Patterson-UTI did not immediately respond to a request for comment, but previously said it's committed to preventing future such accidents. An attorney for Red Mountain did not immediately return a phone call for comment.

The Jan. 23 explosion also killed Matt Smith of McAlester, Josh Ray of Fort Worth, Texas, and Cody Risk of Wellington, Colorado.

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