Murillo was last seen at his residence in the 700 block of north 14th Street in Council Bluffs, Iowa at 6:15 p.m. on November 28, 2009. The day before, his mother had taken him to the doctor because he seemed disoriented. The doctor prescribed an anti-depressant for anxiety, but Murillo's mental condition worsened and he began to hear voices that advised him to eat sugar. He felt that his heart was beating too hard and eating sugar would make it better. He became paranoid and believed someone was following him.

On the evening of his disappearance, Murillo ran outside without a coat or shoes on and vanished. He left his wallet, medication and other belongings behind, and there's been no activity on any of his accounts. He has never been heard from again. Little information is available as to his fate; his case remains unsolved.