A reckless exchange of bullets at a crowded outdoor party in Toronto killed two young people late Monday night in what
the city's police chief described as an unprecedented episode of gun violence.

At least 19 others, including an infant, were injured after bullets from more than one gun were sprayed into the crowd of more
than 200 people at a outdoor barbecue in the city's east end.

"This is the worst incident of gun violence, in my memory, anywhere in North America,'' Police Chief Bill Blair said from the
scene of the crime in a residential neighbourhood.

"It is the most serious crime of its kind that has ever taken place in the city of Toronto.''

Police made multiple appeals for witnesses to contact them as they began to pull together descriptions for what appeared to be multiple shooters.

They said they had one "person of interest'' in custody and were looking for other suspects.

The incident took place before 11 p.m. on Danzig St., near Morningside Ave., and Lawrence Ave. East.

"An altercation broke out among some individuals and there was an exchange of gunfire. During that gunfire a number of innocent bystanders were struck,'' said Blair.

"It's a very shocking event, a lot of people were injured tonight.''

The two killed in the shooting were a teenage girl and a man in his early 20's, officials said.

Blair did not provide the age of the child who was injured but says the injuries are "not life-threatening and the child will be
fine.''

Those hurt in the incident suffered a mix of gunshot wounds and injuries from the mass panic that ensued. Victims were taken to five different hospitals.

A variety of Toronto police divisions were called in to assist with the investigation, including the Guns and Gangs unit and the
homicide squad.