Of the 13 people injured, they range in age from 10 to 59 and have undergone multiple life-saving surgeries, according to the CBC.
Update 6:00 p.m. EDT July 23: Canadian authorities have released the identity of the gunman who allegedly opened fire on a busy street in Toronto's Greektown Sunday night.
Ontario’s Special Investigation Unit identified the shooter as Faisal Hussain, 29, who was killed by police, according to Reuters.
Hussain’s family said in a statement he had “severe mental health problems and struggled with psychosis and depression his entire life.”
"Our hearts are in pieces for the victims and for our city as we all come to grips with this terrible tragedy. We will mourn those who were lost for the rest of our lives,” the statement said.
Update 12:35 p.m. EDT July 23: Toronto police Chief Mark Saunders said the two people killed in Sunday's shooting in Greektown were both girls, one 10 years old and the other 18.
Officials have not released the victims’ names or identified the suspected gunman, who also died Sunday.
Saunders declined on Monday to elaborate on the circumstances surrounding the suspect’s death or his possible motive.
“We don’t know why this has happened yet,” he said. “This investigation is very new, it’s very fluid.”
Thirteen people remained hospitalized Monday after being injured in Sunday’s shooting, Saunders said. The victims ranged in age from 10 to 59 years old and suffered injuries from minor to severe, according to the police chief.
Authorities continue to investigate.
Update 8:05 a.m. EDT July 23: The slain suspect was a 29-year-old man, Ontario's Special Investigations Unit said in news release Monday morning.
The release, citing "preliminary information," said the man "fired shots at groups of people several times" along Danforth Avenue around 10 p.m. Sunday, hitting "several people" and fatally injuring two people.
"Officers located the man on Bowden Street and an exchange of gunfire took place," the release continued. "The man fled the area and was located, deceased, on Danforth Avenue."
The unit, which has assigned three forensic investigators and six investigators to the case, looks into "reports involving police where there has been death, serious injury or allegations of sexual assault," the release said.
Update 7:51 a.m. EDT July 23: A second victim has been pronounced dead after a gunman opened fire late Sunday in Toronto's Greektown neighborhood, Toronto police tweeted Monday morning.
Meanwhile, Canadian Prime Minister tweeted his condolences Monday morning to the victims of Sunday's mass shooting in Toronto.
"My thoughts are with everyone affected by the terrible tragedy on the Danforth last night in Toronto, and may the injured make a full recovery," Trudeau tweeted. "The people of Toronto are strong, resilient and brave – and we'll be there to support you through this difficult time."
Update 2:01 a.m. EDT July 23: Toronto police Chief Mark Saunders said the child in critical condition is an 8- or 9-year-old girl, the Washington Post reported. He described the victim who was killed as a "young lady," according to The Associated Press.
No further information about the condition of the victims was immediately available.
Saunders said the shooter used a handgun in the rampage and was killed after exchanging gunfire with officers. The shooting did not appear to be random, Saunders said.
One witness, John Tulloch, said he heard as many as 30 gunshots, the AP reported.
A video circulating on Twitter appeared to capture the sound of gunfire.
>> Click here to watch (WARNING: Viewer discretion advised.)
Update 1:06 a.m. EDT July 23: The child who was shot, a young girl, is currently in critical condition, according to Toronto police.
Police say it is "too early to say whether the shooting is terrorism," The Associated Press reported.
One city official, Councillor Paula Fletcher, said the shooting was not gang-related. Fletcher and Councillor Mary Fragedakis also said the gunman was emotionally disturbed.
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