STARKE, Fla. (AP) — The execution of a South Florida drug trafficker, convicted of killing a state trooper with a pipe bomb, is on indefinite hold.

The U.S. Supreme Court refused the state's request to lift a stay of execution just hours before Paul Augustus Howell was set to die by lethal injection Tuesday.

The Atlanta-based 11th U.S. District of Appeal on Monday temporarily blocked the execution so it could consider a last-ditch appeal.

The state appealed to Justice Clarence Thomas  who referred the case to the full court.

Howell was convicted of killing Florida Highway Patrol Trooper Jimmy Fulford in 1992 with a bomb placed inside a gift-wrapped microwave oven.

Authorities said it was intended to kill two Marianna women, but Fulford stopped a car carrying the package for speeding near Tallahassee.