Tweets from Toronto police late on Sunday confirmed the shooter is dead.

Police said a nine-year-old girl was among the 14 people shot.

She was said to be in a critical condition.

A video from one witness shows a man dressed in black clothes and a black hat walking quickly and firing three shots from the pavement into at least one shop or restaurant.

Witnesses then heard many shots and described the suspect walking past restaurants and cafes and patios on both sides of the street and firing into them.

Toronto's Greektown is a lively residential area with crowded Greek restaurants and cafes.

Police Chief Mark Saunders said the shooting on Sunday night in the city's bustling Greektown neighbourhood was not random and he did not rule out terrorism as a motive.

"Other than the shooter we have a young lady that is deceased," he told reporters.

The shooter, died from an apparent gunshot wound, but it's not clear if it was self-inflicted or as a result of exchanging gunfire with police, he told reporters.

Witness Jody Steinhauer has told CBC she was at a restaurant on Danforth Avenue with her family when she heard what sounded like 10 to 15 firecracker blasts.

She said she was told to run to the back of the restaurant.

"We started to hear people scream out front," Steinhauer said, adding that she had been told four to six people had been shot.

John Tulloch said he and his brother had just left their car when he heard about 20 to 30 gunshots.

"We just ran. We saw people starting to run so we just ran," he said.

An army of police, paramedics and other first responders soon descended on the scene, while residents, some in their pyjamas, emerged from their homes to see what was happening.

A woman who gave her name only as Mary told the Toronto Star she was in the Pantheon restaurant on Danforth Avenue when she saw a young girl being placed on a stretcher and taken into an ambulance.

Another witness who was standing near the scene told CTV that he heard about 20 shots and the sound of the weapon being reloaded repeatedly.

"And then, I saw the carnage as I ran down the street here to kind of follow the gunfire," the man told the station, who described the scene as "pretty crazy".

Toronto police sergeant Glenn Russell told CNN witnesses were being taken by buses to multiple offices to speak with investigators.

Toronto mayor John Tory told CBC he believed the shooting was evidence of a wider gun problem in Toronto, adding the incident unfolded in a peaceful part of the city and that the community was in shock.

"It's almost inconceivable that these things can happen," Mr Tory said.

"Guns are too readily available to too many people."

Mass shootings are rare in Canada's largest city.

But this past week, Toronto police deployed dozens of additional officers to deal with a recent spike in gun violence in the city.

Mr Tory called the shooting an “unspeakable” incident, and reiterated a police plea for any members of the public who were in the area to come forward with information.

He said there were many people in the area, which is home to several restaurants and bars, at the time of the shooting.

He urged anyone with mobile phone video or eyewitness information to reach out to police.

Toronto councillor Paula Fletcher told CP24 she heard that the gunman was "emotionally disturbed".

"It's not gang related. It looks like someone who is very disturbed," Fletcher said.

Reuters, AP

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