Shots rang out inside the Queen subway station underneath the bustling Eaton Centre mall around 8 p.m. Friday, sending the 18-year-old man to hospital.
Subway rider Kevin Chan described a frightening and chaotic scene onboard the train before the young man was shot.
"It was like people panicking, screaming and then people saying 'get off'... some people were crying," he told local media outlets after the incident.
Carm Piro with the Special Investigations Unit told reporters it's believed four of the nine officers who were on the scene fired their weapons.
"The man has some gunshot wounds. We haven't been able to determine which officer has caused those injuries."
The SIU earlier said the man was in stable condition in hospital but didn't offer an update on his condition. It isn't releasing his name because his family won't consent to it.
Piro said officers were responding to calls from inside the station about a "suspicious person" on a subway train. He said the person had a weapon, but wouldn't elaborate.
He said the four officers have not been interviewed, though three of five "witness officers" have. More than a dozen eyewitnesses at the station have also told investigators their account of the incident and it's hoped others who were there will have video footage, Piro said.
Other witnesses said multiple shots were fired after police ordered a man to drop a weapon. Piro wouldn't comment on the number of shots or the circumstances of the incident, citing the ongoing investigation.
A main leg of the Yonge Street subway line surrounding the station was closed following the shooting, with service resuming for holiday shoppers and other passengers early Saturday afternoon.
The shooting is the second time this year police have used lethal force on city transit.
It comes after the fatal police shooting in late July of 18-year-old Sammy Yatim on an empty streetcar, an incident caught on video that sparked noisy protests and accusations that officers are too eager to go for their guns in confrontations.
An officer faces a second-degree murder charge in Yatim's death, while the police service has also launched a review of its use-of-force policies.
Meanwhile, an ongoing coroner's inquest is looking into the deaths of three Toronto-area residents who were gunned down by police at different times over the past three years.
Coun. Josh Matlow said that while the facts aren't yet in on just what happened during the subway shooting, lethal force should always be the "last option" for police.
"I deeply hope that the results of the SIU investigation show that the police acted responsibly. But if it turns out that they did not then the public would justifiably demand accountability."
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