A spokeswoman for Canada Border Services Agency says a man arriving home via London last Friday was searched more thoroughly when officers became suspicious.
They found that his suitcases contained false bottoms and the way the heroin was hidden was sophisticated.
"Officers X-rayed the bags which revealed an abnormal organic mass. There was 3.3 kilograms in one suitcase and 3.4 kilograms in the other," Candace Lyle, director of border services operations in Calgary, said Thursday.
"Officers noted the false bottoms and tops were made by using parts from identical bags and glued the factory linings over the narcotics."
Officials didn't say where the man was coming from.
Rashid Abdulla Mussa, 44, faces two counts under the Controlled Drugs and Substances Act.
"Our investigation is ongoing right now. We're trying to determine possible points of origin and possible destination points," said RCMP Insp. Gord Sereda.
"Quite frequently we see it is part of a network and that's what we hope the investigation will uncover. Quite often these drugs have a link to organized crime and that's where they generate significant profits."
Mussa remains in custody.
In 2013, customs officers in Calgary seized almost 20 kilograms of heroin.
The methods used by criminals to smuggle in drugs can be ingenious. Last summer, officers discovered five kilograms of black tar opium hidden in seven coffee carafes at the airport. Anyone opening the carafes would have found nothing. The bottoms were removed, the drugs inserted and the bottoms then rewelded to the carafe.
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