TORONTO -- Ontario's police watchdog has concluded there are no reasonable grounds to charge any Toronto police officer with a criminal offence in the shooting of a 34-year-old man late last year.

The incident happened around 1:30 a.m. on Nov. 30, 2013, when officers became involved in a confrontation with a man on the fourth floor of a downtown apartment building (at 177 Mutual Street).

The Special Investigations Unit says the man sprayed one of the officers with dog repellent and then struck him with a fire extinguisher, knocking him down a stairway.

The man ignored orders to drop the fire extinguisher and spray can and moved toward another officer -- who was armed with a rifle -- spraying the can in that officer's direction.

The SIU says that officer fired several rounds, paused briefly, then fired another series of shots, striking the man several times, and that a senior officer then fired a conducted energy weapon at the man.

SIU director Tony Loparco says it has been determined that the officers' actions were reasonable under the circumstances.

"The subject officer believed the man was about to assault him with the fire extinguisher," Loparco said Wednesday.

"He also had concerns about the man taking possession of his C-8 rifle should he manage to incapacitate the officer with the pepper spray and/or a physical attack with the fire extinguisher, and then use the weapon to further threaten those around him."

The SIU says it assigned six investigators and three forensic experts to probe the circumstances of the incident. Five witness officers and 17 civilian witnesses were interviewed as part of the investigation, it said.

The SIU is an arm's-length agency that investigates reports involving police where there has been death, serious injury or allegations of sexual assault.