Jackie Tran leaves his immigration hearing on Wednesday. (CBC)

A rare look at two of Calgary's warring gangs emerged at a deportation hearing for a convicted drug trafficker that's dragged on for more than four years.

Calgary police laid out its case Wednesday against Tran Trong Nghi Nguyen, 26, who goes by the name Jackie Tran, at an Immigration and Refugee Board hearing where Tran is appealing a deportation order.

Sgt. Gavin Walker testified that Tran is a member of a gang called the FOB Killers (FK), and is linked to several people who have been killed or hurt in gang-related attacks.

Walker outlined how a group of friends, who dealt drugs, split into two factions in 1999: the original group called Fresh Off the Boat (FOB), and the FK.

He said that since 2002, at least 12 homicides have been linked to their violent feud.

The gang expert testified that several gunmen tried to shoot Tran in 2005, but he did not co-operate with the police investigation or seek their protection.

When an officer went to Tran's house in 2007 to warn him of another possible attack, the alleged gangster waved him away, saying, "This isn't going to be over until they are all dead. Or we are all dead," according to Walker.

At a hearing last month, Tran admitted being friends with gang members, but denied being one himself. He said he started dealing crack cocaine after dropping out of high school because he had no supervision and no money.

A permanent resident in Canada since 1993, Tran racked up a criminal record in Calgary that includes two convictions for drug trafficking and one for assault with a weapon, leading to the deportation order in 2004.

One of Tran's lawyers, Steve Virk, tried to discredit Walker, pointing out his lack of formal gang education. Virk also emphasized that police have never been able to criminally charge Tran with being a gang member.

Written arguments from Tran's lawyers and the federal government are due by Jan. 26. A decision from the IRB adjudicator is expected shortly after that.