Toronto police continue to hunt for multiple suspects as they try to figure out why a 23-year-old man was fatally shot in front of bystanders outside a busy shopping mall Saturday night.

At a news conference Sunday, homicide squad Det. Rob North said police believe more than one firearm was used in the shooting that killed Michael Nguyen, but they do not know if there was a shootout.

A 24-year-old man who was wounded in the shooting at Yorkdale Shopping Centre is in stable condition in a Toronto hospital and is expected to survive, North said.

No innocent bystanders were wounded in the shooting, which police described as an “isolated” incident involving two groups.

North said there is currently no evidence that the fatal shooting – the second to occur at a Toronto mall in 10 months – is gang related or related to any other "major" incidents in the city.

Both Nguyen and the victim who survived are known to police, he said.

As they review surveillance video, investigators are looking for several people who may have been involved in the shooting, which occurred in the parking lot near the southwest corner of the mall.

Initially, police said they were looking for five or six suspects. On Sunday afternoon, North would only say police are looking for multiple suspects.

Police said the groups got into a fight before gunshots were fired in the parking lot shortly after 8 p.m. Detectives are trying to figure out whether the groups knew each other prior to the shooting.

Nguyen was with at least one other person when he was shot in the roadway near the entrance to a Sears store, North told reporters.

Nguyen died at the scene, becoming Toronto’s 15th homicide victim of 2013.

North would not say whether Nguyen was armed with a firearm, although he did say police have not recovered any weapons during their search for suspects and evidence.

Police have not released descriptions of the suspects.

Outside the mall Sunday, a team of seven forensic investigators pored over the scene for several hours.

Officers looked under vehicles and peered through windows, inspected vehicles for physical damage, wrote down licence plate numbers and took a 3D scan of the parking lot where the shooting occurred. A police dog sniffed around vehicles.

Later, police towed a grey Toyota Corolla that North described as a "vehicle of interest" that is undergoing "further examination."

No reason to live in fear, police say

In an attempt to ease any fears about violence in public places, North said Toronto is a safe city and is no different than any other major city.

North said there is no reason for Torontonians to interrupt their daily routine.

“I don’t think there should be a concern for the public,” North said. “This was a very isolated incident between two groups. We’re not talking about people who come here and shoot random people coming out for an evening with their family.”

Still, the detective urged people to be vigilant and co-operate with the city's police service to prevent further violence.

“These things, while very disturbing to the community, unfortunately happen, and we as a community and we as the police need to work together in a concerted effort to try and minimize these incidents from happening,” North said during the news conference.

Shoppers forced to leave vehicles at mall

After the shooting, officers blocked parking lot exits and set up a large perimeter in an effort to contain the scene as they searched for suspects and interviewed witnesses.

Hundreds of shoppers, including parents with young children, and mall workers were stuck inside the building for hours, as frustrated shoppers waited to learn if they could leave in their vehicles.

Because the parking lot was sealed off, people were forced to leave their vehicles in underground and surface lots overnight.

Just before 3:30 p.m. Sunday, police announced that all vehicles held in the parking lot overnight can now be retrieved. Up to that point, officers had been releasing select vehicles after they were deemed to not be of interest in the shooting investigation.

Diana Coulombe returned earlier on Sunday to pick up her car, but it was still within a taped-off area where police were gathering evidence.

Coulombe said she and her nine-year-old daughter were not allowed to enter the parking lot Saturday night after the shooting.

She said her daughter became upset and cried during the commotion.

Because she couldn’t get to her car, Coulombe and her daughter got a ride home from her husband.

One woman told CP24 she planned to rent a room at a nearby hotel as she waited for police to clear the scene.

The mall is closed for Easter Sunday, but its theatre and restaurants were open Sunday. The mall will open as scheduled Monday, North said.

David Wills, a spokesman for the shopping centre, thanked people for their patience and for co-operating with the police investigation.

Meanwhile, police believe there are several witnesses who have not spoken to investigators.

Anyone with information about the shooting or anyone who was at the mall before the incident is asked to call investigators at 416-808-3200 or Crime Stoppers anonymously at 416 222-TIPS (8477).

Saturday’s violence is reminiscent of a shooting that occurred in the food court at Eaton Centre last year.

Ahmed Hassan, 24, and Nixon Nirmalendran, 22, were killed and at least five others were wounded in the shooting on June 2, 2012.

The suspect, Christopher Husbands, was charged with two counts of first-degree murder and multiple counts of attempted murder.

With files from CP24 reporter Jamie Gutfreund.

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