Edmonton police have revealed that Phu Lam, the shooter in Monday’s mass murder, had a long criminal history that included domestic violence.

Lam’s criminal history dates back to 1987. Neighbours say they often heard screaming coming from the 53-year-old’s house.

A total of nine people were found dead at three separate sites, including two homes and a suburban restaurant, by the time the deadly rampage was over early Tuesday morning.

So far, three victims have been identified in the murders: Lam’s second wife Tien Trong, Cyndi Duong, who worked for Enbridge, and a young child identified as Elvis.

“I would like to stress that this series of events were not random acts, but rather appeared to be planned, deliberate, and targeted,” Edmonton Police Chief Rod Knecht said of the killings.

Autopsies will be conducted Thursday on seven of eight victims, as well as the suspect, in a mass murder that Edmonton's mayor has described as "a devastating case of domestic violence."

On Wednesday morning, a forensic unit remained at a north Edmonton home where seven of the victims, including two children, were found dead.

Timeline of events

Investigators say a male suspect shot one woman at a south Edmonton home Monday night at about 6:50 p.m.

Officers were then called to a north Edmonton home on two separate occasions. The first time, the caller asked for help with a “depressed” and “overly emotional” male family member, but no one answered the door when police arrived. A second, different caller phoned police after midnight, and officers entered the home to find seven dead, including two children.

The next morning, police surrounded a Vietnamese restaurant in the Edmonton suburb of Fort Saskatchewan and found the suspect dead inside at about 9 a.m.

The man was a maintenance worker at the VN Express, according to the daughter-in-law of one of the restaurant’s owners.

She told The Canadian Press he was also her mother-in-law’s ex-husband.

A black SUV found at the restaurant had also been spotted at the south Edmonton home where the first victim was killed, police said.

The 9mm handgun used in the deadly rampage was legally registered in B.C. in 1997, but was reported stolen in 2006.

'Devastating case of domestic violence'

Knecht described the killings as an “extreme case of domestic violence” in a news conference on Tuesday. He said the crime scene where seven bodies were found was “chaotic” and “horrific,” and said he’d never seen anything like it in his 39-year career.

“I know the husband doesn’t live there anymore, but his car’s been there for the last week,” said neighbour Murray Shermack.

Another neighbour said he’s heard yelling coming from inside the home on multiple occasions.

Knecht confirmed that police had been called to the home twice in the past. The first time was in November of 2012, when a man was arrested and charged with offences related to domestic violence, sexual assault and uttering threats, he said.

The second time was in 2013, when police conducted a welfare check, he said.

Knecht said an autopsy has already been performed on the woman shot in south Edmonton. Cyndi Duong, 37, died as a result of a gunshot wound, he said.

Enbridge confirmed that Duong was an employee at the company, serving as a team lead in the regional pipeline supply chain group.

The seven victims at the second crime scene have not yet been identified. Police say there were three women and two men between the ages of 25 and 50. The other two victims were children under the age of 10.

On Wednesday, Edmonton Mayor Don Iveson stopped by the home to leave a bouquet of flowers at a growing memorial outside.

In a statement issued earlier in the day, Iveson said he was "shocked and saddened" to learn of the deaths, noting that residents' hearts "are heavy with the news."

"As more details have emerged, it now seems clear that this is a devastating case of domestic violence," Iveson's statement continued.

"The scale of these events is rare and exceptional. However, domestic violence remains all too common in our society and this tragedy is a harsh reminder of the continuing need for support for individuals and families in crisis, and the critical importance of reporting any instances of domestic violence to police."

Iveson also offered his thanks to police and other first responders who must do their jobs with "courage and focus in otherwise horrific circumstances."

Alberta premier Jim Prentice also responded to the incident.

“I wish to express my sorrow at the tragic incident which claimed lives in Edmonton and Fort Saskatchewan today, and my appreciation to the first responders involved,” he said.

With reports from CTV Edmonton