TORONTO -- Ontario's police watchdog says officers were justified in opening fire on a man who went on a deadly shooting rampage in the Toronto's Greektown last summer and were not responsible for his death.

The Special Investigations Unit says there are no reasonable grounds to lay criminal charges in the death of 29-year-old Faisal Hussain, adding it is satisfied based on the evidence that Hussain took his own life.

In a report released Wednesday, the agency's director, Tony Loparco, says there is no evidence that the officers' actions were "anything but commendable in the face of truly perilous circumstances."

Hussain opened fire in a popular area on July 22 of last year, killing 10-year-old Julianna Kozis and 18-year-old Reese Fallon and injuring 13 others.

The SIU's report says he exchanged fire with officers who arrived at the scene before running away and fatally shooting himself in the head.

The agency says it interviewed 15 civilian witnesses and seven police officers as part of its investigation. It also reviewed surveillance video, in-car camera footage and Hussain's autopsy report as well as a firearms report.

The watchdog says one of the two officers who came to the scene reported fearing for his life after Hussain fired two to four shots in their direction. Forensic evidence shows one officer fired at Hussain three times in response, while the other fired at him once, it says.

Video footage shows Hussain then ran north and west until he disappeared from sight behind a church, the SIU says.

Another officer who was in the area found Hussain lying on his back near the church with a "significant injury to the right side of his head," the agency says. The officer also saw a shell casing next to Hussain's head, an empty magazine on the sidewalk and a black handgun in his right hand, it says.

Hussain's autopsy report concluded that he died from a gunshot wound to the head, an injury that would have immediately incapacitated and killed him, the SIU says.

"Mr. Hussain's death was caused by a single bullet which traversed his brain and it is clear that neither officer is responsible for this wound," Loparco says in the report.

"It would have been impossible for Mr. Hussain to run away as depicted if either officer had caused the injury to Mr. Hussain as observed in the post-mortem report," he says.

"Given the evidence, including the results of the post mortem examination, I instead conclude that Mr. Hussain died at his own hands when he decided to shoot himself in front of the Danforth Church."

There is also no evidence suggesting anyone else shot Hussain, and it appears unlikely that someone could have done so considering he was armed and prepared to shoot, Loparco says.