(AP) — A former prison inmate charged with killing four people in Omaha earlier this year will be evaluated to determine if he is competent to stand trial.

A Douglas County District judge approved the defense request for 27-year-old Nikko Jenkins to be evaluated by state psychiatric experts Monday.

Jenkins has pleaded not guilty to four counts of first-degree murder and 10 weapons counts in the killings that happened within a month of his release from prison on July 30.

But Jenkins has said in recent letters to prosecutors and local media that he now wants to plead guilty to killing 29-year-old Jorge Cajiga-Ruiz and 26-year-old Juan Uribe-Pena on Aug. 11, 22-year-old Curtis Bradford on Aug. 19 and 33-year-old Andrea Kruger on Aug. 21.