The latest homeless victim of a suspected serial killer filed a police report the day before he died, saying he feared he was being stalked.
It was one of nearly 600 leads and tips that officers received, but police didn't have a chance to follow up.
"It is unfortunate that we didn't get to him before the suspect did," Anaheim Police Chief John Welter said.
Itzcoatl Ocampo was arrested Friday night when witnesses chased him down after a man was stabbed to death outside a fast-food restaurant in Anaheim, about 26 miles southeast of Los Angeles, authorities said. He was caught with blood on his hands and face, authorities say.
The Iraq War veteran was charged Tuesday with four counts of murder and special allegations of multiple murders and 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.
Ocampo was due to appear in court on Wednesday, but his attorney said his arraignment would likely be postponed since he was not allowed inside the jail to speak with his client over the weekend and has met with him only briefly.
Defense attorney Randall Longwith declined to comment on the allegations. He said Ocampo is being held in a mental ward.
"I walked in, he was curled up in a blanket," Longwith said. "He looked like a wet puppy dog."
Ocampo selected the last victim, 64-year-old John Berry, after he was featured in a Los Angeles Times story about the killing spree, prosecutors said.
"He was a monster," Orange County District Attorney Tony Rackauckas said at a news conference. "He was a terrible threat, particularly to the homeless people in our community."
Ocampo would stalk each of his victims, then stab them repeatedly with a knife that could cut through bone, authorities said.
Authorities declined to say whether they had identified a motive. Rackauckas said he had no indication that Ocampo was mentally ill.
Ocampo's family said the 23-year-old was a troubled man after he returned from Iraq in 2008.
If convicted, Ocampo faces a minimum sentence of life in prison without parole. Authorities have not decided whether to seek the death penalty.
The killing spree began in December, prompting police and advocates to fan out across the county, which is known as the home to Disneyland and multimillion-dollar beachfront homes, to urge the homeless to sleep in groups or in one of two wintertime shelters.
Ocampo's arrest was the latest violent crime involving a veteran. This month, an Iraq War veteran fatally shot a ranger at Mount Rainier National Park and died later as he fled police across the mountain's snow-covered slopes.
Veterans Affairs officials say such high-profile violence can paint an inaccurate picture of returning veterans. The cases, however, raise the issue of veterans having a difficult time adjusting back into civilian life.
To help, the VA created a program to assist veterans in readjusting to their lives and avoid repeated brushes with the law. "We've seen over and over again that once they access those services, we can help them," VA spokesman Josh Taylor said.
A neighbor who is a Vietnam veteran and Ocampo's father both tried to push him to get treatment at a VA hospital, but he refused. His father, Refugio Ocampo, said, his son came back from his deployment a changed man.
He said his son expressed disillusionment and became ever darker as he struggled to find his way.
After Ocampo was discharged in 2010 and returned home, his parents separated. The same month, one of his friends, a corporal, was killed during combat in Afghanistan. His brother said Ocampo visited his friend's grave twice a week.
Like the men Ocampo is accused of preying on, his father is homeless. His father lost his job and ended up living under a bridge before finding shelter in the cab of a broken-down big-rig he is helping to repair.
Days before his arrest, Ocampo visited his father, warning him of the danger of being homeless. He showed him a picture of one of the slain men, his father said.
"He was very worried about me," his father said. "I told him, `Don't worry. I'm a survivor. Nothing will happen to me.'"
As fear spread through the homeless community, police last week set up road blockades to seek help from members of the public in tracking down a suspect. Ocampo, who appeared to relish the media spotlight, passed through the checkpoints twice but did not draw attention to himself, Rackauckas said.
In addition to Berry, James Patrick McGillivray, 53, was killed near a shopping center in Placentia on Dec. 20. The body of Lloyd Middaugh, 42, was found near a riverbed trail in Anaheim on Dec. 28. The third victim, Paulus Smit, 57, was stabbed to death outside a library in Yorba Linda on Dec. 30.
Associated Press writer Kevin Freking in Washington, D.C., contributed to this report.