This photo provided by the Anaheim Police Department shows Itzcoatl Ocampo. Investigators are "extremely confident" that Ocampo is responsible for all four recent killings of homeless men in Orange County.
An ex-Marine charged with killing four homeless men in north Orange County has been linked to the stabbing deaths of a woman and her son in Yorba Linda, Anaheim police said Thursday.
Investigators determined there is an association between the ex-Marine, Itzcoatl Ocampo, and Eder Herrera, who is charged in the deaths of the woman and her son, and remains in custody, Anaheim police Lt. Julian Harvey said. Police would not elaborate on that association or provide further details.
"We've developed significant evidence that links him to this crime," Harvey told KPCC.
Harvey told KPCC that he couldn't comment on whether Ocampo and Herrera worked in tandem, but that they have info linking Ocampo to the crimes. He added that if, during the investigation, evidence either supports or vindicates Herrera, that evidence will be president to the district attorney's office.
Raquel Estrada and her son Juan Herrera were killed Oct. 25, 2011 in Yorba Linda, less than two miles from Ocampo's home.
"They were stabbed to death inside their home," Harvey told KPCC.
Eder Herrera is Raquel Estrada's 24-year-old son and was arrested soon after the killings. Estrada was in her 50s and Juana Herrera was in his 30s, Harvey told KPCC.
Detectives said Wednesday they saw similarities in the cases of the Yorba Linda deaths and the stabbings of four homeless men in December and January.
Detectives focused on the severity of the attacks, the number and the type of wounds and the proximity of Ocampo's home to the Yorba Linda killings.
Harvey told KPCC that he couldn't comment on details of the evidence in the ongoing investigation. He said that as soon as Ocampo was arrested, police began investigating all other potential crimes Ocampo could be associated with.
Authorities have linked Ocampo to a killing spree targeting four homeless men: James Patrick McGillivray, 53, who was stabbed Dec. 20 near a shopping center in Placentia; Lloyd Middaugh, 42, who was found Dec. 28 near a riverbed trail in Anaheim; Paulus Smit, 57, who was stabbed to death outside a Yorba Linda library on Dec. 30; and John Berry, 64, who was stabbed to death on the day Ocampo was arrested.
Each of the four men was stabbed more than 40 times with a weapon believed to be a 7-inch fixed-blade military-type knife, authorities said.
Before Ocampo's Jan. 13 arrest, police had fanned out across the county better known as the home to Disneyland and multi-million dollar beachfront homes to urge the homeless to be careful and seek shelter indoors.
Ocampo has been charged with four counts of first-degree murder, plus the special circumstances of multiple victims and murder by lying-in-wait.