SANTA ANA (AP) — A former Marine accused of murder in the deaths of four homeless men, a woman and her son has died at a hospital after falling ill in his jail cell.

Orange County sheriff’s Lt. Jeff Hallock says deputies found 25-year-old Itzcoatl Ocampo in his single-man cell Wednesday and he was taken to a hospital. He was pronounced dead at about 1:30 p.m. Thursday.

READ MORE: 'My Son Was Targeted,' Laguna Hills High Student Spouts Racial Slurs At Black Player During Basketball Game

No cause of death was immediately given and an autopsy will be performed in the coming days.

Orange County prosecutors were seeking the death penalty against Ocampo for the slayings of four homeless men between late 2011 and early 2012 in what they called a serial thrill-kill spree.

He also was facing murder charges in the deaths of a school friend’s mother and brother in October 2011.

READ MORE: Ag Startup And Walmart Building Tech-Operated Indoor Farm In Compton

RELATED STORIES:

Iraq War Veteran Charged In Murders Of 4 Homeless Men

Attorney: Ocampo Slammed Head Into Jail Toilet To Stop Hearing Voices

Iraqi War Veteran Accused In 6 Murders Tells Detective He Has ‘Killer Gene’

MORE NEWS: Sheriff's Deputies Investigating Fatal Shooting In San Gabriel

(© Copyright 2013 The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed.)