The father of the Australian man who went on a deadly stabbing spree at a busy Sydney mall on Saturday has a theory as to why the attack targeted women while mostly avoiding men. Joel Cauchi was identified as the assailant who carried out a knife attack in the Westfield Bondi Junction mall near world-famous Bondi Beach, leaving six people dead and more than a dozen injured. Police ruled out terrorism and said Cauchi had a history of mental illness. The killer’s father, Andrew Cauchi, however, said he knew why his son, who had targeted women. He blamed his son’s frustration at not having a girlfriend. “Because he wanted a girlfriend, and he’s got no social skills, and he was frustrated out of his brain,” the 76-year-old told reporters outside his home in Toowoomba in Queensland state, an area approximately 540 miles from the New South Wales border with Sydney. Australian police are continuing to investigate why Joel Cauchi targeted women while avoiding men, a police commissioner said on Monday. New South Wales State Police Commissioner Karen Webb said detectives intend to question Cauchi’s family amid the ongoing investigation. The only male killed was Faraz Tahir, 30, a Pakistani refugee who worked as a security guard at the mall. Tahir was not armed. The five other deceased victims were women. Webb said most of the 12 surviving victims were also women. CCTV footage from the mall specifically showed Cauchi targeting women, she explained. “The videos speak for themselves, don’t they? And that’s certainly a line of inquiry for us,” Webb said. The police commissioner added, “It’s obvious to me, it’s obvious to detectives that that seems to be an area of interest: that the offender had focused on women and avoided the men.” The father, who was visibly distraught when he spoke with reporters, described his now-deceased 40-year-old son as a “very sick boy.” “He’s my son, and I’m loving a monster. To you, he’s a monster. To me, he was a Believe me, he was a very sick boy,” the father added. The deceased victims were identified as Tahir, Yixuan Cheng, 27, Jade Young, 47, Dawn Singleton, 25, Pikria Darchia, 55, and Ashlee Good, 38. Eight victims who survived their injuries remained in hospitals on Monday, including Good’s 9-month-old daughter. Andrew Cauchi told reporters that his son had a “fascination with knives.” The father also said he took five knives, which he described as combat grade, from his son while they were living together in the Toowoomba family home last year. He feared they would be he said. The father explained his son grew angry over the incident and called police, accusing the father of theft. The knives were given to a friend for safekeeping. “I told the police my son had schizophrenia, and I’m worried for myself,” Andrew Cauchi said. “I said to my mate, ‘Why do I feel I’m going to be killed in my own house by my own son with a U.S. combat knife?’” he added. Police shot and killed Joel Cauchi after they responded to the knife attack on Saturday.