LITTLE ROCK — Eight Arkansas inmates who are scheduled to die by lethal injection next month filed a lawsuit Monday asking a federal judge to block their executions.

Also Monday, the state Parole Board recommended that Gov. Asa Hutchinson deny requests from two of the inmates for clemency.

The eight inmates’ suit, filed in U.S. District Court in Little Rock, alleges that the state’s planned use of the sedative midazolam as part of three-drug cocktail in their executions “is all but certain to cause plaintiffs excruciating suffering.”

Executions using midazolam to sedate inmates before other drugs were administered have been botched in Oklahoma and Alabama when inmates appeared to be not entirely sedated during the procedure. The U.S. Supreme Court has upheld the use of midazolam in executions, however.

The state Attorney General’s Office did not immediately file a response to the suit Monday.

The state Parole Board on Monday decided to advise Gov. Asa Hutchinson that the clemency requests of condemned inmates Ledelle Lee and Stacey Johnson are without merit.

Lee, 51, was convicted of capital murder in the 1993 slaying of Debra Reese of Jacksonville. Johnson, 47, was convicted of capital murder in the 1993 slaying of Carol Jean Heath of De Queen.

Both men maintain that they are innocent and that errors occurred in the handling of their cases in lower courts.

The governor is not bound by the Parole Board’s recommendations.

Another condemned inmate, Marcel Williams, asked the board for clemency in a hearing Monday. Two others inmates are scheduled to appear at clemency hearings Friday.

Arkansas has not executed an inmate since 2005 because of legal challenges and difficulties in obtaining execution drugs. The state is rushing to carry out executions before its supply of one execution drug expires at the end of April.