MONTGOMERY, Ala. (AP) — The state of Alabama must seek a new execution date for a condemned inmate if it still wants to execute him following an unexpected postponement.

Prison officials halted preparations for Doyle Lee Hamm’s lethal injection late Thursday because medical staff said they couldn’t find a suitable vein before the execution warrant expired.

The prisoner has argued in court that years of drug use and illness left his veins unusable for authorities to kill him by lethal injection.

The delay means the state attorney general’s office must ask the Alabama Supreme Court for a new execution date if it still intends to execute Hamm.

The attorney general’s office didn’t immediately respond to a message about its plans on Friday.