Police said the incident happened in the area of Mid Way Boulevard and Invader Crescent on August 27.
They arrived to find several people hit by gunshots. An investigation began, and on Wednesday, police executed a search warrant at an unspecified residence and arrested a suspect.
The suspect, identified as 26-year-old Hamsa Mohammed of Toronto, faces nine charges, including two counts of attempted murder and discharging a firearm with intent.
Police continue to ask anyone with information to contact investigators at 905-453-2121 ext. 1233 or Crime Stoppers anonymously at 1-800-222-TIPS (8477).