LINCOLN, Neb. (AP) — A psychiatrist says he doesn’t know why a mentally ill prisoner was released from custody, giving him the chance to kill four people in Omaha.

Dr. Eugene Oliveto told a legislative committee Thursday that he had recommended Nikko Jenkins be placed in a state psychiatric hospital prior to the shooting deaths, but his suggestion wasn’t followed.

Jenkins was found guilty of four counts of first-degree murder in April. Lawmakers have launched an investigation into the state’s handling of the case.

Oliveto says it was obvious to him that Jenkins was mentally ill and dangerous, and he disputed arguments by state psychiatrists that Jenkins is faking his symptoms. Oliveto says Jenkins consistently described the same delusions, including an Egyptian god in his mind who ordered him to kill people.