Chris Doncaster was declared dead at the scene after a shooting inside a house near 25 Sideroad and 9th Line on Tuesday evening, which also claimed the lives of two South Simcoe police officers. The Special Investigations Unit initially did not officially identify the shooter, only stating that he was a 23-year-old living in the house. However, on Wednesday, several family friends and an ex-girlfriend of the deceased confirmed to CTV News Toronto that the 23-year-old was Chris Doncaster after identifying him. Neighbors also said Doncaster was the grandson of an elderly couple who lived in the house. CTV News Toronto learned that Chris Doncaster was the suspect in the fatal Innisfil, Ontario incident after a shooting that killed police officers.

"He was definitely a troubled kid," one neighbor told CTV News Toronto, adding: "You don’t know the details of what happens behind closed doors, but he was very disturbing. I am disturbed thinking about what the grandparents must be feeling now about their grandson and everything that happened in that house." Also, John Van Dyke, Chief of South Simcoe Police, identified the fallen officers as Devon Northrop, 33, and Morgan Russell, 54, during a Wednesday afternoon press conference, where the police released photos of both officers. Northrop had served with Simcoe Police for six years, while Russell had 33 years of service experience. Northrop was a member of the mental health crisis outreach and support team and the emergency response unit. Additionally, Russell was assigned to a uniform patrol and was a trained crisis negotiator. Van Dyke said the service asked York Regional Police to investigate the circumstances of the incident, stating: "We must acknowledge that the Ontario Special Investigations Unit (SIU) has jurisdiction, so I am very limited in the information we can share." In the same vein, authorities earlier said the two officers responded to a disturbance call at a house near 25 Sideroad and 9th Line just before 8 p.m. Family members inside the house made the call. Upon arrival, the Special Investigations Unit said there was an exchange of gunfire between a 23-year-old man from the house and the officers, who later died after being shot.