Updated

A man ate cleanser that he apparently collected slowly while in custody and died while awaiting trial in the killings of four homeless men and two others, his lawyer said.

The lawyer, Michael Molfetta, who was briefed on the death, said Friday that the incident raises serious questions about Orange County jail deputies' supervision of Itzcoatl Ocampo, who was mentally ill.

Ocampo, a 25-year-old former Marine, was found shaking and vomiting in his single-man cell Wednesday and taken to a hospital where he was pronounced dead a day later, sheriff's Lt. Jeff Hallock said.

No cause of death was immediately given, and officials said an autopsy will be performed in the coming days, but Molfetta said investigators believe Ocampo waited until he accumulated enough Ajax industrial cleaner for a lethal dose, then ingested it.

The district attorney's office will investigate the death and autopsy results by an independent pathologist are expected by the middle of next week, Hallock said.

"If you spend three minutes with Ocampo, you are acutely aware of the fact that he has some mental issues. They were severe and they were obvious and they definitely were not contrived," Molfetta said. "This was a guy who should have garnered the highest level of scrutiny."

Hallock declined to comment on inmate supervision or the attorney's account except to say jail deputies are required, in general, to walk by each inmate's cell a minimum of once an hour.

But Hallock did say that staff giving inmates cleaning supplies for their cells was common practice at the jails.

"It would not be out of the ordinary for an inmate to be provided with a small amount of powdery cleaning product," he said. "It would be typically enough for one cleaning."

Marie Middaugh, mother of victim Lloyd "Jimmy" Middaugh, said in a phone interview that she was relieved with Ocampo's death.

"A trial wouldn't have brought our loved ones back," she said. "I'm sorry things happened the way it did for his family because I know they're grieving, too, but I'm just glad that really it's all over."

Someone at a number listed for Ocampo's father hung up repeatedly when a reporter called Friday.

Prosecutors alleged that Ocampo, a native of Mexico, stabbed four homeless men in what they called a serial thrill-kill rampage in late 2011 and early 2012. Ocampo targeted his homeless victims because they were vulnerable and because he felt they were a blight on the community, authorities said.

He was charged in January 2012 with four counts of murder, with special allegations of multiple murders, lying in wait and use of a deadly weapon. Three victims were stabbed more than 40 times each with a single-edged blade at least 7 inches long. In one instance, prosecutors, said, Ocampo selected as his next victim a homeless man who was featured in a Los Angeles Times story about the killings.

Ocampo, who was discharged from the Marines in 2010, also was facing murder charges in the deaths of a school friend's mother and brother in October 2011.

At the time, his family said Ocampo was a troubled man after he returned from Iraq in 2008 and he went to visit the grave of a friend who died in combat in Afghanistan twice a week. He also began drinking heavily and he suffered from headaches and hand tremors, they said.

His parents separated in 2010 and his father became homeless after losing his job. During the killing rampage, Ocampo visited his father on the streets and warned him about the dangers of being homeless, even showing him a picture of one of the dead men.