HELENA, Mont. (AP) — A civil-rights organization suing Montana over its execution method says a recent Ohio execution illustrates the dangers of using untested drug combinations in lethal injections.

Dennis McGuire gasped and snorted as he took 26 minutes to die in Thursday's execution.

Montana last year changed its lethal-injection combination from three drugs to two, though they are different drugs from those used in Ohio.

But American Civil Liberties Union of Montana attorney Anna Conley says Montana's two-drug combination also has not been tested and nobody is sure how it will work.

The ACLU is representing two death-row inmates who are asking a judge to rule Montana's execution methods are unconstitutional.

Montana Department of Corrections spokeswoman Linda Moodry says the state's execution protocol is distinct from that of other states.