LITTLE ROCK, Ark. — A federal judge dealt a serious blow Saturday to Arkansas’ unprecedented plan to execute eight inmates in an 11-day period, saying the men have the right to challenge a drug protocol that could expose them to “severe pain.”

The state appealed U.S. District Judge Kristine Baker’s order hours later, hoping to follow through with its planned executions, with the first scheduled for Monday. Arkansas’ supply of one of its three lethal injection drugs, midazolam, expires April 30 and Republican Gov. Asa Hutchinson has said he wants to use the drugs before they spoil.

Manufacturers object to states using their drugs in executions, and the Arkansas Department of Corrections said in previous court filings that it doesn’t have a way of obtaining more of the sedative midazolam.