Toronto police are seeking a fourth person in connection with a shooting during Monday鈥檚 Raptors celebrations that injured four people and set off a panic in the crowd.

During a scrum with reporters on Tuesday, Toronto Police Chief Mark Saunders said investigators were looking for a 鈥減erson of interest鈥 who he described as a white male between 5鈥9鈥 and 6鈥 feet tall with short light-brown hair and a heavy build. Saunders said the man was wearing a white button-down shirt and was last seen running westbound on Queen Street West.

鈥淭here were definitely people that were there that saw and would probably have no idea in connecting the dots -- that鈥檚 the person that we鈥檙e looking for,鈥 he said.

Three suspects were arrested and two firearms were recovered soon after shots rang out at approximately 3:30 p.m., just after the Toronto Raptors team arrived at Nathan Phillips Square for a rally in honour of their NBA championship win. 

Shaquille Anthony Miller, 25, Abdikarim Kerow, 18, and Thaino Toussaint, 20, of Toronto all appeared at Old City Hall court Tuesday at 10 a.m. on charges for firearm offences. Kerow鈥檚 charges related to a prior warrant for his arrest, police said in a statement. 

Saunders said police are also looking for the gun involved in the shooting because the shell casings at the scene don鈥檛 match the two firearms they already recovered.

鈥淲hen we look at the casings, which identify that a gunshot has occurred, they鈥檙e not matching right now, on first blush, the guns that we have seized,鈥 he said.

The shooting occurred at the back of the square near Queen Street West and Bay Street and caused crowds of fans to flee in panic.

Several witnesses said they were trampled by other scared attendees who were rushing to escape the scene of the shooting.

Miriam Valdes-Carletti was one of those fans who was caught in the middle of the chaos moments after the shooting.

鈥淚 was standing right by the Toronto sign, pretty much in the middle of all of it, and all of a sudden I heard a rumbling, sort of like there was a herd of animals coming towards us and everyone turned around and we were just like whiplashed and trampled all over,鈥 she recalled to CTV鈥檚 Your Morning on Tuesday.

The young woman said she fell to the ground, but a woman grabbed her arm and helped her up as people fled for safety.

鈥淚t was just really scary. There were kids crying, like holding their moms. There were other people screaming 鈥楧on鈥檛 lose me! Don鈥檛 lose me!鈥欌 she said. 鈥淭here were just so many people.鈥

Valdes-Carletti said she didn鈥檛 see any police officers as she ran. However, Toronto Police Const. David Hopkinson said there was a 鈥渧ery large police presence in the area鈥 where the shooting occurred, which allowed them to reach the victims and suspects quickly.

The four victims all suffered non-life-threatening injuries, according to Saunders.

The police chief said he doesn鈥檛 yet have enough information to determine a possible motive behind the shootings.

鈥淚t鈥檚 still early with respect to magnitude of the occurrence and the situation and the amount of things that have to be combed through,鈥 he said.

Saunders said they have already received video evidence and information that led to the arrest of a few suspects. He asked that any other witnesses 鈥渟tep up and help us鈥 by uploading any vidoes or photos to . Witnesses can also call police at 416-808-5200 or contact Crime Stoppers.

鈥淭he biggest thing we're looking for is witnesses because we can't have two million people in a small space and say nobody saw anything,鈥 he said.

Security concerns

As the city appeared to return to normalcy on Tuesday, questions have been raised about the level of security at the event.

Brad Ross, the chief communications officer at the City of Toronto, said Monday鈥檚 parade and rally were intended to be positive events.

鈥淲e need to remember this is about celebration, not keeping people back, but allowing people to have fun,鈥 he explained.

Ross said the police presence throughout the day was at the discretion of the Toronto Police Service and he could only comment that there were security measures in place.

鈥淲e had barricades along the route. The barricades were essentially ignored by the fans,鈥 he said. 鈥淲ere they everywhere on both sides of the street? I don鈥檛 believe they were, but they were certainly along key pieces of the route.鈥

The safety of fans became a concern when crowds gathered on the street only metres away from the double-decker buses carrying the Raptors, which caused significant delays throughout the parade.

鈥淧eople surged onto the street and I think that鈥檚 something that鈥檚 part of our post-mortem and debrief on this event is what might we be able to do differently next time,鈥 Ross said.

CTV Public Safety Analyst Chris Lewis said police tried to find the right balance between keeping people safe and maintaining a positive atmosphere.

鈥淚f you get too restrictive then people start trying to violate that and that causes other problems,鈥 he told 麻豆影视 Channel. 鈥淚f you鈥檙e too strict in terms of taking action on some people that are maybe walking out on the street that shouldn鈥檛, you have to really balance that out and not create arrests and fights and problems you鈥檇 rather not have.鈥

Lewis said he thought city officials and emergency crews did an 鈥渆xcellent job鈥 of organizing and monitoring the celebrations throughout the day.

鈥淭hey didn鈥檛 have a real blueprint because they鈥檝e never had two million people in the City of Toronto like that,鈥 he said. 鈥淭hey know how to do these things very well, they were just overwhelmed with the size of this to some degree.鈥

On Tuesday, Toronto Mayor John Tory said yesterday was a 鈥済ood day鈥 for the city, despite the 鈥渞eckless actions鈥 of those who brought guns to the event. He said city officials would use the experience to ensure 鈥渘othing but the best鈥 for future such events.

鈥淥ur City Manager Chris Murray will be working with Police, the TTC, other city departments and our sports teams to review the details of yesterday's parade & see how we can improve,鈥 .