STARKE, Fla. (AP) — Following a slew of conflicting court rulings, a federal appeals court has blocked the scheduled execution of a mass killer convicted of eight killings that jolted South Florida in the 1970s. The U.S. Supreme Court upheld the stay.

The 11th U.S. Circuit Court of Appeals' decision Tuesday came during a flurry of legal decisions over claims that 64-year-old John Errol Ferguson suffers from mental illness so severe he cannot be executed. Ferguson, a paranoid schizophrenic with delusions he's the "prince of God," had faced a planned lethal injection at 6 p.m. Tuesday in Florida's death chamber.

The appeals court set a schedule for motions that will likely delay the execution at least until the first week of November, if not longer.