A 20-year-old man was shot following an altercation with two men and two boys at Thorncliffe Park Drive and Overlea Boulevard on Monday evening.
Initial reports had suggested two people had been shot, but police say just one person was shot and one of the arrested parties was stabbed.
The victim was shot once in the lower body, police say. He was taken to hospital with non-life-threatening injuries.
Following the shooting, police reported that four suspects had fled the scene.
Police say they have since arrested an 18-year-old man and two underage males. Each of these individuals face 10 criminal charges, including attempted murder.
Police say they are looking for an additional 18-year-old male on a single charge of attempted murder. Gavin Patrick Campbell is considered armed and dangerous. If spotted, police say members of the public should call 911.