ATMORE, ALA. ? A murderer who would have become the nation’s first executed inmate in months won a reprieve Thursday from the U.S. Supreme Court a little more than an hour before he was scheduled to die by lethal injection.

James Harvey Callahan, set to die at 6 p.m. CST, was granted a stay, Holman prison warden Grantt Culliver told officers on death row. The Supreme Court’s brief order did not detail why it granted the stay.

It would have been the nation’s first execution since September, when the high court agreed to consider whether lethal injection is cruel and unusual punishment. The inmate’s attorney had asked the high court to halt the execution after a federal appeals court lifted a stay granted by a Montgomery judge.

Callahan was sentenced to death for the 1982 murder of Jacksonville State University student Rebecca Suzanne Howell, who was abducted from a coin laundry and raped before being strangled and dumped in a creek.

Her mother, Verna Coheley, and sister, Karen Greer, had arrived to witness the execution. A corrections officer quoted them as saying it was “cruel and unusual” for them to get there only to learn of the stay, said prison system spokesman Brian Corbett.

The Supreme Court on Sept. 25 agreed to hear a challenge filed by two Kentucky death row inmates over that state’s lethal injection method. No U.S. executions have taken place since then, except for one that occurred in Texas just hours after the decision was made.

Callahan challenged Alabama’s method of lethal injection, which like most capital punishment states is similar to Kentucky’s. The Atlanta-based 11th U.S. Circuit Court of Appeals ruled Tuesday, however, that he waited too long to do so.