06/05/2012 03:59 EDT | Updated 08/05/2012 05:12 EDT

Stabbing Prompted Eaton Centre Shooting, Sources Say

Toronto Police Handout

The man killed in the deadly Eaton Centre shooting in Toronto that left six other people wounded apparently stabbed the suspect three months ago, CBC News has learned.

Ahmed Hassan, 24, died in the Saturday evening shooting that plunged the landmark mall in downtown Toronto into chaos as thousands of shoppers fled in terror.

Hassan and another man, a 23-year-old who can't be identified due to a publication ban, were the suspected targets of the shooting, police said Monday.

The episode left five other innocent bystanders — including a 13-year-old boy — wounded and forced the evacuation of the mall.

Christopher Husbands, 23, of Toronto, has been charged with one count of first-degree murder and six counts of attempted murder. Husbands, Hassan and the 23-year-old man who was wounded were all part of the same gang, police say, although they haven't provided any more specifics.

Despite the gang affiliations, police don't believe the shooting was gang-motivated; rather, "personal aspects" were at play, according to Det. Sgt. Brian Borg.

CBC News has now learned more about what may have precipitated the shooting.

Sources say that the shooting may have been an act of retribution, as it appears Hassan stabbed the alleged shooter in March while robbing him.

Hassan himself had survived two previous attempts on his life, CBC News has learned. Hassan faced drug charges in Fort McMurray, Alta. — he was charged with cocaine trafficking in January 2010 along with five other people.

He was also charged with obstructing a police officer and possession of stolen goods.

One of Hassan's co-accused, a 19-year-old man from the Toronto area, was killed three months later in a Fort McMurray apartment.

The victim's father, Abdul Kadir Ali, told CBC News that Hassan was a suspect in the death of his son, Abdinasir Dirie.

Hassan was out on bail at the time for the alleged forcible confinement of another Fort McMurray man, Jama Ahmed Mahamoud, in September 2008.

Hassan fled Alberta last year for Toronto. Hassan failed to appear in court on the cocaine trafficking charges, and at the time of the Eaton Centre shooting, there were two outstanding warrants for his arrest.

Meanwhile, CBC News has learned that the 23-year-old man who was wounded was accused of robbing teens at gunpoint in Toronto's Riverdale Park in 2007. When police arrived on the scene, they shot and killed his accomplice, according to sources.

Meanwhile, at the time of the Eaton Centre shooting, Husbands was under house arrest for a sexual assault charge, for which he is due to appear in court on June 25.

He is expected to appear in court on Aug. 15 for the Eaton Centre shooting.

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