Father of slain children in Australia mass shooting 'still loves' alleged shooter Aaron Cook said he "still loves" his father-in-law, the suspected shooter.

The father of the children who were among those killed in Australia's worst mass shooting in decades came forward to publicly grieve his family and express love for the alleged killer -- his own father-in-law.

Aaron Cockman, a local carpenter and builder, said he was the estranged husband of Katrina Miles, the mother of the four children who were shot and killed, allegedly by her father, Peter Miles, before authorities believe he turned the gun on himself.

"I still love who Peter was and, as I said, if it wasn't for him I wouldn't have Katrina, I wouldn't have any kids," Cockman said. "So it's not some random guy off the street who's taken them away from me. He gave them to me and now he's taken them away.

"If it had to happen," he added, "there is no better person than that."

Police arrived to the family farm early Friday, where they discovered the bodies of Peter Miles, the four children -- Taye, 13, and sons Rylan, 12, Arye, 10, and Kadyn Cockman, 8 -- Katrina and her mother and Miles' wife, Cynda.

The children were believed to be asleep when they were shot.

"All the kids died peacefully in their beds," Cook said. "How the hell Peter did that I still can't figure out, but he did a good job, he did a really good job."

Cook said in addition to still feeling a fondness for Miles, he is experiencing "tremendous sadness for my kids."

The killings were the country's deadliest mass shooting since the Port Arthur Massacre in 1996 when a gunman killed 35 people in Tasmania. The fallout from that incident caused the country to rewrite its gun legislation.

Authorities were still investigating the shooting Sunday.

"This is a complex criminal investigation," Western Australia Police Commissioner Chris Dawson told Channel 9 News, and detailing that each was dead of apparent gunshot wounds inside the Miles' Osmington residence, which is 13 miles northeast of the popular tourist town of Margaret River.

The Western Australia Police Force officers found three firearms -- all belonging to Peter Miles, whose body was also found at the scene.

"Police are not searching for any other subject," Dawson added.