Father of Calif. killings suspect is also homeless (AP) - Just days before being arrested, a Marine veteran suspected in the deaths of four homeless men in Southern California visited his father, who is himself homeless, warning of the danger of being on the streets and showing him a picture of one of the victims. "He was very worried about me," Refugio Ocampo, 49, told The Associated Press on Sunday. Nothing will happen to me.' The father also said his son came back a changed man after serving in Iraq, expressing disillusionment and becoming ever darker as his family life frayed and he struggled to find his way as a civilian. His 23-year-old son, Itzcoatl Ocampo, is awaiting charges in connection with the serial killings of four homeless men since late December. He was arrested Jan. 13 after a locally known homeless man, John Berry, 64, was stabbed to death outside a Carl's Jr. restaurant in Anaheim. Bystanders gave chase, and police made the arrest. Refugio Ocampo said that on Jan. 11 his son came to him with a picture of the first victim, 53-year-old James Patrick McGillivray, who was killed on Dec. 20. "'This is what's happening,'" the father quoted his son as saying. Itzcoatl Ocampo had been living with his mother, uncle, and younger brother and sister in a rented house on a horse ranch surrounded by the sprawling suburbs of Yorba Linda. At the humble home, his mother, who speaks little English, tearfully brought her son's Marine Corps dress uniform out of a closet and showed unit photos, citations and medals from his military service. The son followed a friend into the Marine Corps right out of high school in 2006 instead of going to college as his father had hoped. That same month, Itzcoatl Ocampo's friend, Cpl. Claudio Patino IV, 22, of Yorba Linda, was killed in combat operations in Helmand province, Afghanistan. "Once he received the news he was never the same," said the suspect's younger brother, 17-year-old Mixcoatl Ocampo. He said his brother visited Patino's grave twice a week. Refugio and Mixcoatl both described a physical condition Itzcoatl suffered in which his hands shook and he suffered headaches. He and his two sons went to get haircuts together just a day before the arrest, the father said. In the past few years he lost his job, ran out of savings, lost his house and separated from his wife. Standing near the truck where he sleeps, the father fought back tears as he described the changes he saw in his son in the year since returning home. A school friend, Brian Doyle, portrayed Itzcoatl Ocampo as a fun-loving teen who liked to hit on girls when he joined the military. After he was discharged and returned home he became isolated and trusted no one, Doyle, 23, said in an interview with The Associated Press. "He went from being a tall, geeky kid, really fun-loving...," he said, trailing off. "Everyone's got their issues, you know," he said. In addition to Berry and McGillivray, Lloyd Middaugh, 42, was killed near a riverbed trail in Anaheim on Dec. 28; and Paulus Smit, 57, was found dead outside a Yorba Linda library on Dec. 30. Prosecutors have yet to file charges.