Arkansas Department of Correction spokesman Solomon Graves said Wednesday night that the state had not obtained a new supply of vecuronium bromide, which is the second of three drugs used in Arkansas' lethal injection protocol.
Pulaski County Circuit Court Judge Alice Gray in Little Rock has granted a temporary injunction in favor of the drug supplier McKesson Corp.
The state Supreme Court on Monday lifted Griffen's order and prohibited the judge from considering any death penalty-related cases.
A state prison official testified that he deliberately ordered the drug a year ago in a way that there would not be a paper trail, relying on phone calls and text messages, the AP news agency reported.
According to the Associated Press, Supreme Court Justices rarely upend a lower court order in death penalty cases.
Arkansas contends it must act quickly because one of the drugs in its lethal injection mix, the valium-like sedative midazolam, expires at the end of April.
The Department of Correction had planned an earlier pair of executions Monday and similarly moved condemned inmate Don Davis to the Cummins Unit over the weekend.
A death row inmate scheduled to be executed in an Arkansas prison today was granted a stay by the highest court in the U.S. state hours before his lethal injection, his attorneys said. The attorney for Davis and Ward requested stays of execution until the US Supreme Court rules on an upcoming case concerning defendant access to independent mental health experts.
Attorney General Leslie Rutledge's office filed a 33-page response in opposition to the inmates' application, calling the application another attempt to manipulate the judicial process.
"Today, our court gives uncertainty to any case ever truly being final in the Arkansas supreme court", Justice Rhonda Wood wrote in a dissenting opinion.
Four of the eight inmates have received stays on unrelated issues.
But the state is pressing ahead with its efforts to put the men to death in back-to-back lethal injections Thursday night at its Cummins Unit in the town of Grady, about 75 miles southeast of Little Rock.
One of the inmates set to die Thursday, Stacey Johnson, says advanced DNA techniques could show that he didn't kill Carol Heath, a 25-year-old mother of two, in 1993 at her DeQueen apartment.
The possibility that justices could continue sparing the lives of the remaining killers scheduled to die this month has left death penalty proponents wondering how much longer executions will remain in a holding pattern.
One of the two executions set for Thursday has been halted by the Arkansas Supreme Court, according to CBS affiliate KTHV.
Thursday's double execution is scheduled to start around 7 p.m., barring intervention through any of several ongoing lawsuits.
A federal appeals court had rejected their arguments after a district judge had sustained them.
Lee and Johnson both faced setbacks Tuesday in their quest to get more DNA tests on evidence in hopes of proving their innocence. Attorneys for the inmate filed a request Wednesday for a stay with the state's highest court.
"I have ultimate respect for the court and I'm not going to question individual decisions but I would say there is frustration among the Legislature as to the court's continued refusal to allow an execution to go through", said Sen. The state originally wanted to put to death eight men in 11 days but that is down to five after the two won stays Monday and a third was earlier put on hold by a federal judge.