(CNN) -- A federal judge halted the execution of convicted strangler Jeffrey Landrigan on Monday, hours before he was set to die by lethal injection.
U.S. District Court Judge Roslyn Silver issued the stay four days after Landrigan's lawyers filed a civil rights complaint alleging the planned execution violated his constitutional rights to be free from cruel and unusual punishment and to due process. Landrigan had been set to be put to death on Tuesday at noon MT (2 p.m ET).
In 1989, Landrigan escaped from an Oklahoma prison where he was serving time for second-degree murder. He was convicted of killing Chester Dean Dyer in Arizona a year later, during an armed burglary, and a trial judge sentenced him to death.
The U.S. district court issued its decision, which is a temporary restraining order, after concluding that the state did not provide Landrigan's side enough information to sufficiently make its case about the safety and legality of substances that would have been used to kill him.
The court had asked state authorities to provide "detailed information concerning the sodium thiopental" that would be used to execute Landrigan. Members of the Arizona Department of Corrections provided some of this information, but they "never provided any information" about the efficacy of the substance and wanted to ensure any information did not become public, according to the U.S. District Court document.
"(The state authorities) refused to disclose... any information regarding the drug ... even after a direct court order requiring 'immediate' disclosure," the court ruling said.
Arizona Attorney General Terry Goddard said Monday evening that his office would appeal Judge Silver's ruling to the U.S. Court of Appeals for the 9th Circuit. If that appeal fails, Goddard vowed in a statement to appeal to the U.S. Supreme Court.
In that statement, Goddard said the state Department of Corrections lawyers provided details on the quantity and expiration dates of the substance. But they did refused to name the producer, citing Arizona law that prohibits disclosing the "identity of executioners" or companies or people party to an execution.
"Jeffrey Landrigan was appropriately sentenced to death, and his victims are awaiting justice," Goddard said.
Landrigan's lawyers said the drug was not approved by the U.S. Food and Drug Administration -- something that the state admitted when it said the the substance did not come from Hospira, which the plaintiff said was the only federally approved company that produced sodium thiopental. The judge ruled Monday that it is not necessarily illegal for non-FDA approved drugs to be used in an execution, a small victory for the state.
But the judge's ruling dismissed the state's claims this was a "condemned prisoner's last-minute attempt to manipulate the system."
In Arizona, a combination of three drugs -- sodium thiopental, pancoronium bromide and potassium chloride -- are used to kill death row prisoners by lethal injection. No one has been executed in Arizona since 2007, and Gov. Jan Brewer had denied to issue a reprieve to Landrigan.
Without a stay, Landrigan would have been "executed in 18 hours using a drug of unknown quality that was obtained from an unidentified, non-FDA approved source," Judge Silver said in her ruling.