A federal appeals court issued a stay of execution for a convicted killer who was to die this week in Tennessee's first electric chair execution in 46 years.

Daryl Keith Holton, who confessed to the assault rifle slayings of his three young sons and their half-sister, had chosen this year to stop appealing his death sentence, but suddenly decided to resume appeals.

He had been set to die Tuesday.

Kelly Gleason, a post-conviction defender working with Holton, confirmed on Monday the stay issued by the 6th U.S. Circuit Court of Appeals and also acknowledged she typed and sent a handwritten petition from Holton to the U.S. Supreme Court requesting that his execution be stopped.

"We discussed it and I filed it over the weekend," Gleason said.

In granting the stay, the 6th Circuit said it wanted to review the district court's ruling that Holton's lawyers failed to prove he is not competent to abandon federal appeal of his sentence.

The court also noted the stay was necessary in light of Holton's filing to the U.S. Supreme Court. In that petition, Holton claims he was "denied a fair trial due to the ineffective assistance of trial counsel."

Hours after the 6th Circuit ruling, the Tennessee attorney general's office filed a motion with the U.S. Supreme Court to vacate the stay. But the U.S. Supreme Court declined later in the day to lift it.

Holton, 44, decided to be put to death in the electric chair rather than by state's preferred method of lethal injection. Tennessee allows death row inmates to choose between the two execution methods if their crimes were committed before 1999.

Holton has said he was severely depressed when he committed the murders. His lawyers maintain he has a long history of mental illness and may suffer from post traumatic stress disorder from his military service in the 1991 Gulf War.

Corrections officials said Holton was moved back to death row from a holding cell near the execution chamber.

Dorinda Carter, spokeswoman for the state Department of Correction, said prison officials expect it to take at least couple of weeks for anything to happen in Holton's case. Under Tennessee state regulations, a new execution date must be set by the state Supreme Court.

Nine U.S. states allow some or all condemned inmates to choose between lethal injection and another execution method, according to the Death Penalty Information Center. Ten states have the electric chair, but only Nebraska uses it exclusively.