Calgary's police chief says even though the leader of the notorious FOB gang is currently behind bars while he awaits trial there is still a lot of work to do to prevent future violence in the city.

Nick Chan was arrested in July on charges of first-degree murder and instructing a criminal organization.

"I don't want anyone to think that gang violence is over," Rick Hanson said on the Calgary Eyeopener this morning.

  • Listen to his full interview below:

Hanson is proud his officers were able to lay charges against several high-ranking gang members in Calgary — most of whom are facing murder charges — but he says it leaves a void and other gangs could move in.

He said Calgary police are working with counterparts across Canada to know which gangs are trying to set up shop in the city.

"The reality is ... there is violent, nasty people in the world today," said Hanson. "When there is money at stake and a market at stake they will do whatever they need to do to take over the market."

Hanson said the goal is for the gang unit and suppression team to intervene early to help prevent a war like the one that gripped the city over the last decade.

He said once a gang has established itself it is much more difficult to fight it. He said there is a "code of silence" among members where they refuse to talk to police and instead take matters into their own hands in revenge-fuelled killings. 

The fight between the FOB and FK gangs has been linked to at least 25 deaths in Calgary since 2002.

Formed in the late 1990s, the FOB — which initially stood for "Fresh Off the Boat" — would eventually became one of the most violent criminal organizations in Calgary. Rival group FK, or "FOB Killers," was later established after personal rifts between FOB members split the group.

'Locking them up is the solution'

Most of the top-ranking founding members of the FOB have either been killed, are in custody or have made plea deals.

Hans (Jay) Eastgaard, 37, has been granted full immunity in exchange for his testimony against others in the notorious FOB gang.

CBC News obtained court documents earlier this week that show the attorney general of Alberta will not prosecute Eastgaard for three slayings and two attempted killings.

"The complexity of organized crime today means that you have to use every technique, every tactic that is legal and at your disposal, to target these groups," said Hanson. 

Another gang member, Michael Roberto, also received partial immunity in June when he became a police witness.

Roberto was involved in several murders and has provided authorities information about how the murders took place and which gang members were present. The information from the former gang members led to a series of arrests in July.

Hanson says the use of informants can be risky but police work closely with the Crown prosecutor under strict rules.

"If it means you can put the untouchables in jail, the ones that are masterminding killings.... If you can get them in jail, that's a great thing because that's the only way you can truly impact gangs and be able to reduce the levels of violence."

He said while violence does continue inside correctional institutions it is easier to control. He credits Alberta's prison guards with good work on that front.

"Locking them up is the solution," said Hanson. "When they're in jail they are not hurting anyone outside."

Because the animosity is so great between the two groups, FK members are sent to the Drumheller Institution while FOB members are incarcerated at Bowden Institution.

The FOB has also formed alliances with native gangs — the Red Alerts and Alberta Warriors — inside the Calgary Remand Centre and other Alberta prisons.

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