Officials with the Special Investigations Unit give an update on an officer-involved shooting that resulted in the death of a 19-year-old man in Mississauga.
The province’s police watchdog is investigating after a Peel police officer shot and killed a 19-year-old man who allegedly stabbed a family member in their Mississauga residence on Thursday afternoon.
The Special Investigations Unit (SIU) said a resident on Greensboro Drive near the area of Winston Churchill Boulevard and Britannia Road called Peel police at 2:30 after finding an injured 39-year-old man inside their home.
“It was later determined that that man had been stabbed by a family member at a neighbouring residence,” SIU spokesperson Kristy Denette told reporters at the scene.
mississauga stabbing Police and paramedics respond to a call on Greensboro Drive in Mississauga on Thursday, Dec. 11, 2025. (Jacob Estrin)
As a result, tactical and K9 officers responded, and when they entered the injured man’s residence nearby, they encountered a 19-year-old man believed to be behind the stabbing in the basement, Denette said.
She noted that police informed the SIU that the man had an edged weapon at the time.
“There were some negotiations, and then it was followed by an interaction with police,” Denette said. “There was a taser that was deployed, and following that, there was an officer who shot the man.”
Denette said the man was subsequently taken to the hospital, where he was pronounced dead.
She added that the officer who fired their gun was also transported to the hospital, albeit as a precautionary measure. Denette did not believe the officer sustained physical injuries.
“The stabbing occurred in a neighbouring residence, and it involved family members. So, there’s no threat to public safety, and there’s no additional people who have been injured that we’re aware of,” she said.
mississauga stabbing Police and paramedics respond to a call on Greensboro Drive in Mississauga on Thursday, Dec. 11, 2025. (Jacob Estrin)
Denette noted that the stabbing victim is in the hospital, but did not provide any update on his condition.
As to the circumstances that led to the stabbing, she said she did not have any information regarding that. While the SIU will look into the shooting, Peel police will investigate the stabbing, Denette said.
When asked how many times the officer fired their gun, Denette said the SIU did not have that confirmed at this time
“All we kind of have right now is what the police have told us,” she said.
The SIU has assigned three investigators and three forensic investigators to the case, and a post-mortem is being scheduled.
Mississauga stabbing and shooting Peel police are on the scene of a stabbing and officer-involved shooting at a home in Mississauga on Thursday, Dec. 11, 2025. (Jacob Estrin/CTV News)
No subject official and witness officials have been designated, but Denette said a total of seven officers were in the residence during the shooting.
“I do know that there is body-worn camera footage. However, it’ll take some time for the SIU to gather that footage and review it. It’s still quite early,” she said.
“(SIU investigators) will be canvassing for witnesses. We’ll be wanting to talk to the man in hospital if he’s in condition to be able to provide us a statement, that sort of thing. And then the body-worn camera footage.”
The SIU is an independent government agency that investigates police conduct that may have resulted in death, serious injury, sexual assault and/or the discharge of a firearm at a person.