STOCKTON  (AP) — A California family counselor suspected of killing his estranged wife and two of her relatives before he committed suicide had been in a contentious divorce that included a fight over property valued as high as $1 million, a defense attorney said Wednesday.

Divorce proceedings between suspect Colin McGrattan, 45, and his estranged wife, Jackie Arata, 57, had been tense and focused on Arata's family ranch in nearby Linden, attorney Dennis Duncan, who represented Arata, told The Associated Press.

Police suspect McGrattan killed Arata, her sister, Kathleen Arata, 64, and their aunt, Chizuko Kanieshi, 88, before killing himself on Monday in Stockton, police said. McGrattan and Kanieshi died in a senior home.

A call to McGrattan's attorney, Michael Babitzke, was not immediately returned.

Duncan said Arata inherited orchards and a home from a family trust, and McGrattan thought he had a claim to the property valued between $500,000 and $1 million. They had leased the orchards to farmers and lived in the home until their separation in October 2010.

McGrattan thought he was entitled to the property after the couple had taken care of Arata's mother prior to her death in 2010, Duncan said.

"Colin's position was that he had some right to the ranch," the lawyer said. "But Jackie didn't want him to have any part of it. She was entitled to a sole and separate ownership."

Police say the motive for the killings remained under investigation.

Officer Joe Silva, a police spokesman, said it was unknown where the killing spree began, but investigators suspect McGrattan killed Jackie Arata on Monday afternoon then drove her minivan to Kathleen Arata's home where he fatally shot her.

Police suspect McGrattan then drove to the senior home where he killed Kanieshi in her room before shooting himself in the head. Police later discovered Jackie Arata's body wrapped in a tarp inside her van.

As a counselor, McGrattan mediated arguments between squabbling couples and helped parents and their children through behavioral issues. He and his wife have two teenage sons.

His roommate, Courtney Bradford, told KOVR-TV that she was well aware of his woes.

"As long as I've known him, he's been very kind," she said. "He was talking to me a lot about losing his home and bankruptcy and the money, lawyer for all the divorce court stuff."

Duncan said two boys are now left without their parents.

"Very sad to see a family destroyed like this," Duncan said. "I can't believe something like this has happened."