A former Marine who is suspected of killing four homeless men in Orange County, California recently visited his homeless father to warn him of the dangers of living on the streets.

Refugio Ocampo, 49, told The Associate Press that his son, Itzcoatl Ocampo, visited just days before being arrested on Friday.

"He was very worried about me," Refugio Ocampo said. "I told him, 'Don't worry. I'm a survivor. Nothing will happen to me.'"

He said his son showed him a photo of James Patrick McGillivray, the first homeless victim, who was killed on Dec. 20 at the age of 53.

"This is what's happening," Itzcoatl Ocampo reportedly told his father.

The Iraq war veteran was finally caught on Friday when shoppers at a CVS store in Anaheim saw the murder of 64-year-old John Barry in progress.

"I was in CVS, I was next in line when a gentleman came in and said, 'The serial killer is out there, I need help,'" a male witness, who wished to remained anonymous, recalled to KTLA.

"He stabbed him at least 7 times, that I saw, but he was stabbing him before I even got there," the man said. "I kept yelling, 'Hey stop! Hey stop!' He wouldn't stop."

Responding to the 911 call, police caught up with Itzcoatl Ocampo in a mobile home park.

"We are extremely confident that we have the man who is responsible for the murders of all four homeless men in Orange County," Anaheim Police Chief John Welter explained at a press conference over the weekend.

Refugio Ocampo said that his son had returned from Iraq a changed man. In 2010, a high school friend who had convinced Itzcoatl Ocampo to join the Marine Corps was killed in Helmand province, Afghanistan.

"Once he received the news he was never the same," Itzcoatl's 17-year-old brother Ocampo lamented.

Watch this video from KTLA, broadcast Jan. 16, 2012.