Toronto police have identified two people killed in a mass shooting Monday night at a community barbeque in Scarborough but officials say they need the public’s help to solve one of the worst incidents of gun violence in the city’s history.

Fourteen-year-old girl Shyanne Charles and 23-year-old man Joshua Yasay were innocent victims who were caught in the crossfire of a possible gang fight, Toronto's police chief said Tuesday.

Police Chief Bill Blair, who called it the worst case of gun violence the city has experienced, said the double homicide victims were among 26 people, including a toddler, injured when at least two people armed with handguns exchanged fire at the crowded event.

Homicide Det. Sgt. Graham Gibson told reporters at a news conference Tuesday afternoon, that witnesses have been coming forward with information but that investigators need all the information they can get.

"There is no doubt there are persons in attendance who know the identification of those responsible for the murders and woundings," he said. "These people who attended the party -- that's who we are appealing to."

Police believe the shooters targeted each other and there is a strong indication the two are associated with gangs, Blair said at a news conference Tuesday, where he updated the number of victims and urged witnesses to contact homicide detectives to help them to make arrests.

Without anyone in custody, police are worried about the potential for retaliatory violence. To prevent further violence, Blair said, police are putting additional officers in the neighbourhood and any other neighbourhood where they suspect retaliatory violence may occur.

"Those who are witnesses, make your family, friends and neighbourhoods safe by speaking with the homicide squad," Gibson said.

Gibson asked witnesses to upload their photos and videos to a dedicated website run by the homicide unit.

"The homicide squad encourages people to include personal details but it's not mandatory," he said. "Any witnesses who want to talk to me directly, call me."

Police have not released descriptions of the suspects, although they say they have identified a person of interest and they recovered a firearm at the scene.

Youngest victim a toddler

The shootout occurred as more than 100 people attended a block party on Danzig Street, near Morningside Drive and Lawrence Avenue, at about 10:40 p.m.

Police confirmed 26 people in total were injured as a result of the gunfire. Of those 26, two died from their injuries, 23 suffered gunshot wounds and one person was trampled.

Blair said the youngest victim was a 22-month-old child, who suffered a "grazing" injury and is expected to recover.

The oldest victim is 33 years old.

One of the survivors remains in hospital in critical condition, while the others suffered less serious injuries and are expected to recover, Blair said.

Police did not release the identity or gender of the injured victims.

Blair would not say how many gunshots were fired.

"More than one individual may have been struck by a single bullet," he said.

Friends of the two homicide victims are expected to gather tonight at the crime scene for a candlelight vigil in honour of their friends.

Shyanne Charles, a Toronto resident, was an outgoing girl who liked to smile for the camera. Friends remembered her as a friendly and popular girl who participated in programs at the Scarborough Boys and Girls Club.

Joshua Yasay, Ajax resident, was also active in the community, coaching basketball for kids in Malvern and opening up a business with his friend in the area.

Mayor: Toronto is 'safest city in the world'

At separate news conferences, Blair and Mayor Rob Ford faced questions about a spate of high-profile shootings this summer and concerns about public safety in Toronto.

In an attempt to ease people's fears, both said they consider Toronto a safe city for residents and visitors, with Ford calling Toronto “the safest city in the world.”

Ford described the shooting as a "horrible tragedy" and an "isolated incident." The mayor visited police at the scene of the shooting and said he was bothered when he saw shell casings and discarded objects on the ground.

He later called for the city to declare a war on gangs and also urged residents to co-operate with police.

"We must use every legal means to make life for these thugs miserable, to put them behind bars, or to run them out of town," he said. "We will not rest until being a gang member is a miserable, undesirable life."

Blair, who appeared visibly shaken at the crime scene Monday night, said Tuesday Toronto is "a safe and liveable city."

However, he told reporters Monday night that this was the worst case of gun violence he had seen in his 35 years of policing.

Gun violence and public safety in Toronto has been under intense scrutiny this summer after deadly shootings in public places, including one in Eaton Centre's crowded food court on a busy Saturday and another on a Little Italy patio.

People who live in the area of Danzig Street said a handful of shootings have occurred in that neighbourhood in recent months. Several residents who spoke to CP24 called for an end to the violence.

“Basically, it sickens me,” said a man, who declined to provide his name. “It never used to be this way. The new players in the game are playing it wrong. It’s got to stop and unless change is made it’s gonna get worse.”

Barbecue was held for children: organizer

Shannon Longshaw, who helped to organize the barbecue at a TCHC complex, told reporters the event began in the afternoon for neighbourhood children, with soccer balls and school supplies being given to the kids who attended, and there were no problems before the shooting occurred.

Police were called to the event earlier in the day to investigate noise complaints, Blair said.

Longshaw said people continued to arrive as organizers cleaned up at 9 p.m., the time the barbecue was scheduled to end.

Eugene Jones, who took over as president and CEO of the TCHC a month ago, said the barbecue was not sanctioned by his agency.

As mostly young people were in attendance, a chaotic scene erupted when gunshots rang out. Frantic parents tried to find their children in the crowd and people scrambled for their lives.

Partygoers fled in all directions to escape the gunfire – some thought they were hearing the sound of fireworks at first – and people who live in the area opened their doors to wounded victims and other strangers seeking a place of safety.

Melissa, who lives in the area, said she called three girls into her house, including a 14 year old who was shot in the arm.

Melissa said her neighbour took in a girl who suffered four gunshot wounds.

“There were just people shot everywhere,” Melissa said.

A person who was shot in the back staggered to a nearby laundromat. Paramedics transported 16 people to hospital. At least one person was trampled.

As daylight broke Tuesday morning, objects and evidence strewn across a wide area painted a picture of the mad scramble.

The ground was covered in discarded objects, medical supplies – including bloody bandages, latex gloves and packaging – used by paramedics as they treated and assessed victims at the scene, and yellow markers used by forensic investigators as they scoured the scene for evidence.

Given the number of victims and the significant number of witnesses who were present at the barbecue, police officers have a massive investigation in front of them as they attempt to lay criminal charges. Homicide detectives are leading the investigation, but several other units are involved, including the guns and gangs task force and emergency task force.

Anyone with information about the suspects is asked to call homicide detectives at 416-808-7400 or Crime Stoppers anonymously at 416-222-8477.

With files from CP24’s Sue Sgambati, Katie Simpson and Nathan Downer

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