New details emerge about fatal shooting of 2 police officers in Innisfil, Ont.

Ontario's police watchdog has revealed new details Thursday about a shooting at a home north of Toronto thatleft two police officers and a young man dead.

The Special Investigations Unit (SIU) says the South Simcoepolice officers died in hospital and the 22-year-old man died at the home after an exchange of gunfire Tuesday night in Innisfil, Ont.

In an email Thursday, SIU spokespersonKristy Denettetold CBC News that "based on preliminary information" the two officers who were killed had not drawn their guns when they were shot.

"A third officer who was also at the house exchanged gunfire with the man," Denette said, adding that the suspect was armed with anSKS semi-automatic rifle. The SIU previously listed the man's age as 23, but later corrected that to say he was 22.

A spokesperson for the watchdog says police were called to the home by family members at the residence and that an autopsy for the man is scheduled for Friday.

The South Simcoe Police Service has identified the slainofficers as Const. Devon Northrup who worked with outreach and mental health teams and Const. Morgan Russell, a trained crisis negotiator.

A vigil was held Wednesdaynight at theInnisfil Community Churchto honour the lives of the officers.

Links to armed forces

Residents who live in the area have expressed shock at what happened and have said an elderly couple who had an adult grandson lived in the house where the shooting took place.

The SIUsaid it will not be releasing the suspect's identity at this time without permission from his family.

However, CBCToronto has learned that Christopher JosephDoncaster,whose 23rd birthday falls on Oct. 23, was living with his grandparents,Donna RoseDoncaster, 76, andGlenDoncaster, 83,who are theowners of thehomewhere the shooting took place.

Neighbour Tom Wilson said he was outside speaking with Glenn Doncaster around 5 p.m. the night the shooting took place.

He said he was getting ready to leave when Doncaster said, "Oh, there's Chris" as his grandson pulled up in his truck.

Wilson said he was friendly with his neighbours across the street, and never saw any indication of problems or violence.

He said he hasn't spoken with either of his neighbours since the incident.

"It's gotta be hard," Wilson said.

In an email to CBC News, a Department of National Defence spokesperson saida person by the name of Christopher Doncasterwas a member of theCanadian Forces from May to December of 2020.

The spokesperson said Doncaster was a private with no deployment history who had not finished basic training.

In addition, CBC Toronto reviewed financial records that show Doncasterowed approximately $46,000on a 2020 GMC Sierra 1500. A silver truck that wasthe same make and model was towed by police from the shooting scene Wednesdayafternoon.

Those records also list him as living at the home where the shootings occurred.

Difficult days for police force

South Simcoe Staff Sgt. David Phillips told reporters Thursday that the small police force of 102 uniformed officers is feeling the weight of the killings.

"It's been an incredibly difficult past couple of days. We're getting through it with the support of our community," he said.

"This is like any small workplace, you know everyone."

Plans are currently underway for a police funeral for both Northrup and Russell, Phillips said, adding that the service is also setting up a book of condolences on its website.

Mark Baxter, president of the Police Association of Ontario, said the deaths of the police officers have sent shockwaves through the policing community.

"It's a tremendous loss for our entire policing family," Baxter told CBC Radio's Metro Morning Thursday.

"We may really never understand or know the 'why' but hopefully investigators can get some more information and some more background that maybe can give the families and the officers' colleagues some closure."

Baxter said he felt a sense of disbelief that this is happeningagain in the province. Northrup and Russell are the third and fourth police officers to be killed in Ontario in the last month.

On Sept. 12, Toronto Police Const. Andrew Hong was killed in what police called an "ambush" during a series of shootings that killed two others and wounded three more.

On Sept. 14, York Regional Police Const. Travis Gillespie died at the scene of a head-on car crash.