The department says the accused are all alleged to have been involved in a street rivalry between two gangs.
Media reports have identified those gangs as the FOB and its rival, the FOB Killers.
In one of the killings, gunmen opened fire at a Calgary restaurant on New Year's Day 2009, killing two gang associates and an innocent bystander, Ken’i Su’a.
Four people had previously been charged in that shooting, with two awaiting retrial, one appealing and the other being convicted.
Now first-degree murder charges have been laid against Nicholas Cypui Chan, 35, and Dustin Duke Darby, 30.
Both men are also charged in the 2008 shooting of Kevin Steven Anaya, 21, who was the victim of a drive-by shooting while walking to a home.
Others charged in that case are Timothy Chan, 32, and Nathan Lawrence Zuccherato, 26.
Zuccerato and Van Thoai Luc, 25, are charged in the deaths of Tina Kong and Kevin Ses, who were shot at a restaurant while eating with two friends that same year.
Police say Ses was a loose associate of a gang member but Kong had no connection to illegal activity.
This police operation, dubbed Desino by investigators, began in January 2012 with officers from major crimes, organized crime and community policing.
"The service relied on the assistance of more than a dozen law enforcement agencies and partners from coast-to-coast who lent valuable resources and time and intelligence," said the police department.
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