OKLAHOMA CITY — Oklahoma's highest criminal court unanimously agreed Friday to halt all of the state's scheduled executions after its prison system received the wrong drug for a lethal injection this week.

The Oklahoma Court of Criminal Appeals granted the state's request and issued indefinite stays of execution for Richard Glossip, Benjamin Cole and John Grant. Oklahoma Attorney General Scott Pruitt requested the stays to give his office time to investigate why the state's Department of Corrections received the wrong drug just hours before Glossip was to be executed Wednesday.

Prison officials who opened a box of lethal drugs two hours ahead of Glossip's scheduled execution realized they received potassium acetate instead of potassium chloride, the third drug utilized in Oklahoma's lethal injection formula. After prison officials notified Oklahoma's governor and attorney general, Gov. Mary Fallin issued a 37-day stay of execution for Glossip to give the state more time "to determine whether potassium acetate is compliant with the execution protocol and/or to obtain potassium chloride."

The court ordered the state to provide status reports every 30 days, "including any proposed adjustments to the execution protocol."

Oklahoma's execution protocols were overhauled after last year's botched execution of Clayton Lockett, who writhed on a gurney and struggled against his restraints before being declared dead more than 40 minutes after the procedure began.

On Thursday, Oklahoma Department of Corrections Director Robert Patton insisted that those new protocols were properly followed. But the attorney general expressed concerns about the department's ability to properly carry out an execution.

"Until my office knows more about these circumstances and gains confidence that DOC can carry out executions in accordance with the execution protocol, I am asking the Oklahoma Court of Criminal Appeals to issue an indefinite stay of all scheduled executions," Pruitt said in a statement after requesting the stays on Thursday.

In a separate ruling Friday, the court denied Cole's request to halt his execution over claims that he is insane. Cole's attorneys also made a separate challenge to the state's three-drug formula part of their arguments. They said midazolam, the first drug in the lethal injection formula, is a benzodiazepine rather than an ultra-short acting barbiturate called for in state law.

Cole was set to be executed Oct. 7 for the 2002 killing of his 9-month-old daughter, and Grant was scheduled to die on Oct. 28 for the 1998 stabbing death of a prison worker at the Dick Connor Correctional Center in Hominy.

Glossip, whose execution had been rescheduled for Nov. 6, was sentenced to die for ordering the 1997 beating death of his boss, Barry Van Treese, the owner of the Oklahoma City motel where Glossip worked. Glossip has maintained his innocence.

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