A Toronto man has been charged with several violent crimes including four counts of first-degree murder in a sweeping investigation connecting almost a dozen unsolved cases from last year.

Toronto police announced on Wednesday they laid 54 firearms-related charges as they released details on the secretive "Project Summit."

Police say the investigation linked a series of shootings and homicides which had taken place in Toronto between June and November 2010.

"The results of this investigation are important. It also demonstrates … the incredible negative impact that a single individual can have on our communities," Chief Bill Blair told a press conference on Wednesday.

"The amount of violence that it is alleged that this individual has perpetrated in our city, the victims who have lost their lives as a result of a single person's activity, really reveal to us the importance that we leave no stone unturned."

The investigation connected the deaths of four Toronto men – Jahmeel Spence, Courtney Facey, Mike James and Carl Cole – to a series of robberies and shootings.

Police believe Spence, a 27-year-old father of one who was shot outside an apartment complex at Lawrence Avenue and Bellamy Road on Sept. 10, 2010, was a case of mistaken identity.

Facey and James were killed in an apparent drive-by shooting in an alleyway in the Weston Road and Lawrence Avenue West area on Sept. 29, 2010.

Cole was shot multiple times outside an apartment on Greenbrae Circuit, just north of Lawrence Avenue East and Markham Road, on Nov. 24, 2010.

Homicide Det. Hank Idsinga said there seemed to be no "rhyme or reasons" for the deaths of Facey and James, while Cole was killed following an alleged dispute with the suspect.

He said the suspect was a dangerous man who "proclaims himself to be a gangster."

The suspect did not appear to have any gang affiliations, but appeared to have taken pleasure from his alleged actions, Idsinga said.

"If these allegations are proven in court, he is an evil man," Idsinga told the press conference.

Idsinga said the suspect has been in police custody since March 2011, when he was arrested in connection to a shooting inside a downtown nightclub.

Mark Garfield Moore, 27, of Toronto has been charged with 54 firearms-related offences, including four for first-degree murder.

He was scheduled to appear in court at 1911 Eglinton Ave. E on Wednesday.

Three other men were also arrested as part of "Project Summit" and have been charged in connection to an alleged firearms and ammunition trafficking ring.

The Toronto Drug Squad also charged three people with trafficking controlled substances.

Further details on those arrests were not released at Wednesday's press conference.

Moore raps under the name Prezidenteeh. In videos posted to YouTube, he can been seen waving stacks of money and showing off his jewelry.

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