OKLAHOMA CITY (AP) -- A psychiatrist who examined a man accused of fatally stabbing his father, the state's former labor commissioner, says the defendant suffers from paranoid delusions and is mentally incompetent to stand trial for first-degree murder.

An Oklahoma County judge on Wednesday did not make a determination on Christian Costello's competency, but ordered him returned to a state mental hospital to be examined by another psychiatrist hired by prosecutors.

Costello delivered a rambling minute-long diatribe during the hearing. He admitted killing his father, former Labor Commissioner Mark Costello, saying he was a "hit man" and the killing was part of a "military operation."

Prosecutors say Costello repeatedly stabbed his father at an Oklahoma City restaurant in August 2015. He is charged him with first-degree murder.

Another hearing is scheduled for Oct. 12.