Naveed Shahnawaz, died Friday after being shot outside a nightclub in the CNE. (Toronto Police Service)

A 19-year-old man has died after a shooting in downtown Toronto last week which is being probed by Ontario's police watchdog.

Naveed Shahnawaz, of Brampton, Ont., died in hospital early Friday morning, said Toronto Police in a statement. Shahnawaz succumbed to the injuries he sustained during the shooting five days ago outside Musik nightclub in the grounds of the Canadian National Exhibition.

The shooting occurred when patrons were leaving the nightclub, and got into an altercation in the parking lot, according to the Special Investigations Unit. The SIU investigates all incidents involving police in which death or serious injury occur, or when allegations of sexual assault are raised.

One man with a gun opened fire. Two people were wounded, and a third person was injured, but not by gunfire. After responding and arriving on scene, police officers discharged their firearms at a Honda Accord as it left the area.

On Monday, three men were charged in connection to the Feb. 10 shooting.

An 18-year-old Toronto man has been charged with several gun-related charges, including attempted murder with a firearm and robbery while armed with a firearm.

Another Toronto man, 19, faces charges including dangerous operation of a motor vehicle and assault with a weapon and a third Toronto man, 26, was charged with assault.

Police say an autopsy for Shahnawaz will be scheduled.

Shahnawaz's death has triggered the homicide squad to take over the investigation.