The joint investigation was launched by Vancouver police and the RCMP after 75 overdose deaths last year involving the synthetic opioid fentanyl, a painkiller 50 to 100 times more powerful than morphine that dealers mix with heroin, oxycodone and other drugs.
"We went to the source and began working our way up from the street dealers to those who were supplying fentanyl throughout our communities on a massive scale," said Vancouver police Supt. Mike Porteous.
He said the operation, called Project Tainted, significantly disrupted the drug trade locally and throughout British Columbia.
Police seized heroin, cocaine, marijuana, methamphetamine, counterfeit oxycodone, steroids and hashish as well as vehicles, weapons and cash, executing 11 search warrants.
The announcement came a day after police and health officials issued a warning to drug users about the dangers of fentanyl.
The B.C. Coroners Service has said most people who die from using fentanyl are recreational users, not addicts.
"Drug traffickers want to distinguish their product," said Chief Supt. Kevin deBruyckere of the RCMP.
"The stronger it is, the more profit they can make, the more they can increase their sales. That's why we're seeing fentanyl given the power it has."
He said Vancouver is known as a transnational hub for drug trafficking, with powdered fentanyl imported from Asia and pressed into pill form.
"What we're seeing right across western Canada is green pills with markings similar to oxycodone that are comprised of fentanyl cut with caffeine or other products."
Police said lab tests, which had yet to be performed on some of the confiscated narcotics, would provide more information about the amount of fentanyl they contain.
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