The Special Investigations Unit has released its findings on two high-profile fatal shootings and in both cases, investigators have concluded Toronto police acted properly.

Alwy Al Nadhir, 18, was shot and killed by a police officer on Oct. 31, 2007, in Riverdale Park. 

On Feb. 16, 2008, Byron Debassige, 28, was shot during a confrontation with police in Oriole Park, near the Davisville subway station.

In the Al Nadhir shooting, investigators concluded the man was shot after struggling with a police officer for control of the officer's service pistol.

Police had added extra patrols to Riverdale Park in anticipation of increased problems on Halloween night, including concerns over robberies by teens against other teens.

In the time leading up to the shooting, four robberies had already been reported.

Officers were told by a victim that he had been robbed by Al Nadhir and an another suspect.  The witness said that one of the men was holding a gun.

The two officers, with their service pistols drawn, surprised Al Nadhir and the man in the process of allegedly robbing two other men of their cellphones, jewelry and other valuables.

When police told the suspects to lie on the ground, Al Nadhir refused and fled on foot, but was stopped by one of the officers.

In the struggle that followed, Al Nadhir tried to wrestle the revolver out of the officer's hand.

 "While struggling to hold Mr. Al Nadhir with his left hand, the officer tried to use his service pistol to strike him in order to stop Mr. Nadhir from struggling," said SIU director James Cornish in a news release.

"Mr. Al Nadhir did not stop. Indeed, he grabbed the gun and then the struggle became one for control of the officer's gun. The officer could not pull the gun away from Mr. Al Nadhir and feared that he was going to lose control of it completely."

Al Nadhir was shot and killed in the struggle.

Investigators said a pellet gun resembling a nine- millimetre semi-automatic pistol was found at the scene, along with a black rubber facemask which was around Al Nadhir's neck.

In the Debassige case, police were called to the area near Davisville Avenue and Yonge Street to investigate an armed robbery at a food market.

When they caught up with Debassige in nearby Oriole Park, investigators say, Debassige "reached into his pocket, pulled out a knife with a three-inch blade and pointed it towards them."

Debassige refused repeated calls to drop the weapon and came toward the officers "while wielding the knife in a threatening posture," said the SIU news release.

"A clear picture emerges from the eyewitness evidence gathered in this case, from police and civilian witnesses alike, which is remarkably consistent and compelling," said Cornish.

"The evidence establishes that each officer shot Mr. Debassige believing it necessary to protect himself and his partner from death or grievous bodily harm."

The SIU is called in to investigate any incident in which a member of the public is seriously injured or killed by police.