Flowers and stuffed animals lay on the sidewalk as police continue to investigate the scene where multiple shooting deaths occurred in a north Edmonton home, in Edmonton, Alta., on Wednesday, December 31, 2014. Police have identified the eight people who were gunned down in Edmonton earlier this week by a man who then killed himself.

Image Credit: THE CANADIAN PRESS/Jason Franson

EDMONTON - What was it that made Phu Lam so angry that he killed eight people?

The Edmonton maintenance man had been accused two years ago of abusing his wife and lashing out when he realized their eight-year-old son wasn't his biological offspring. He shot them both Sunday, along with other members of his wife's family, including a three-year-old niece. Yet he spared two other children who had also been in the north-side home — his toddler daughter and an infant nephew.

Lam dropped the two kids off at a relative's home the next day, then visited with other family before driving to another house to kill one final target. When that person wasn't home, he shot dead an innocent woman who happened to be there.

Police revealed the details Friday and said they are still working to piece together the complex case and explain what turned 53-year-old Lam into a cold-blooded killer. All they can say for now is that it involved domestic troubles.

Court documents show Thuy Tien Truong, 35, had tried to escape her marriage to Lam in 2012.

He had emigrated from Vietnam in 1979 and was visiting his home country when he met Truong in a coffee shop in 2000. They married six months later and she came to Canada in 2003. He sponsored her family to come as well in 2009.

Truong said in a 2012 application for an emergency protection order that her husband became controlling shortly after she landed here. Lam changed her phone number because he didn't want her to have friends. He wanted to choose her clothes. He didn't want her to work, but she got a job anyway.

Then he hit her. Once, he choked her so hard she thought she was going to die, she said. He threatened to kill her if she called police.

Truong said in the document she was so unhappy she once had sex with another man. Lam became suspicious and ordered a DNA test that proved that their son, Elvis, was not his.

Lam planned to "actually kill off her whole family and he was going to look for a gun, but no one would sell it to him," a court interpreter said while translating Truong's testimony during an emergency protection hearing.

"He asked his ex-wife if she could find him a gun ... but the ex-wife told him not to do it because he has two kids with his ex-wife too."

Truong testified Lam showed her parents the DNA results and they begged him to forgive her for the affair. She said he sexually assaulted, punched and choked her when they were alone that night. Her sister eventually called police.

A judge granted the protection order, but it was revoked two months later when Truong failed to show up at court. Criminal charges against Lam — assault and sexual assault, and uttering threats against various family members — were stayed. Prosecutors have said the main complainant and other witnesses on the file recanted their stories.

The couple eventually had another child but other court documents filed last year when Lam applied for bankruptcy indicate they separated as early as February 2013. Police said they were still trying to determine if Lam and Truong were living together at the time of the massacre. Lam was listed as the owner of the house and police said he probably still had a key. Other members of Truong's family also lived there.

Police said Lam managed to get a handgun that had been stolen in 2006 in Surrey, B.C.

Acting deputy police chief Mark Neufeld told reporters Friday that autopsies confirmed that all seven people in the family home had been shot to death, probably between 3:45 a.m. and 8 a.m. Sunday — after Truong had finished a late work shift and before she and her mother, 55-year-old Thi Dau Le, were to show up for some morning overtime work. Another relative arrived at the house that morning and knocked on the door, but no one answered.

The other victims in the house were: Truong's father, Van Dang Truong, 55; friend Viet Nguyen, 41; sister Thanh Ha Thi Truong, 33, and her daughter, Valentina Nguyen.

Neufeld said it's not clear if all of them were killed at the same time or if some were shot as they showed up at the home over the course of the morning. He said the two children Lam delivered to other relatives — his and Truong's one-year-old daughter and her sister's eight-month-old boy — were likely in the house during the carnage.

"And yes, for whatever reason, the two children were spared."

Neufeld said police cannot account for Lam's whereabouts right after that. They do know he visited a different relative in southwest Edmonton late Monday afternoon, left there shortly after 6 p.m., and made the short drive to the home of Cyndi Duong, 37.

He was looking for someone else and shot her instead.

"Why, I don't know," said Neufeld, adding that Duong's husband and three children were there at the time.

"She was simply an innocent victim of all this."

He said that although there was no direct link between Duong and Lam, there was some relationship between their families and it's possible Lam knew Duong's father.

Two hours after police received a call about this shooting, a relative of Lam's called to report he was suicidal. Officers went to his home but found nothing suspicious and no one answered the door. They left, returned a few hours later after receiving more information, and discovered the bodies.

A manhunt began. It ended early Tuesday when police found that Lam had shot himself in his ex-wife's restaurant in nearby Fort Saskatchewan. One of her relatives said he worked there as a maintenance man and had access to the building after hours.

Lam's bankruptcy documents show he was in money trouble and on stress leave from another job where he worked as a machinist. The documents suggest he had a gambling problem, as he had attended a recovery program for gambling addicts.

Other court records detail Lam's criminal past. He was fined $200 for an assault in 1989 and handed 90 days in jail for gun and drug charges in 2001. That same year, he was fined twice for communicating with prostitutes. Other charges on his criminal record, such as assault with a weapon and production of a controlled substance, were withdrawn over the years.

Neufeld said investigators received valuable help from the Vietnamese community in sorting out the crime, but added they may never fully understand why Lam exploded so violently.

"We struggle to try to put some sense to something like this," he said.

"We will chase down everything we can to try to find out the reasons why, because I think it's important.

"But at the end of the day you try to import rational thought into an irrational act and, a lot of times, it just never comes."

News from © The Canadian Press, 2015