Police say around 1:15 a.m. Saturday, officers were called to a large gathering in the area of Pack Road and Grand Oak Cross for a person with serious injuries.
The 18-year-old victim was rushed to hospital with life-threatening injuries that were caused by a gunshot, police say.
The victim was pronounced dead shortly after.
Police said Saturday night that the investigation is being treated as a homicide.
No arrests have been made.
Pack Road remains closed between Colonel Talbot Road and Homewood Lane as police continues to investigate.
Anyone with further information is asked to call the London Police Service at (519) 661-5670 or Crime Stoppers at 1-800-222-TIPS (8477).
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