Delta Police allege a huge drug bust in Greater Vancouver shows a new kind of business model for dealers in their quest to make big profits.

It involves the potentially-fatal drug fentanyl, which is being sold to users as heroin. Police are calling it the largest fentanyl bust in British Columbia, and one of the most sophisticated operations they’ve ever seen.

Police discovered the counterfeit heroin through an undercover drug trafficking investigation over an eight-month period. On March 17, two men were arrested after search warrants were executed at residences in Surrey, Richmond and Burnaby.

"It's very, very profitable to take a cheap, strong drug like fentanyl and be able to use it in a method that would look like counterfeit heroin," said Chief Const. Neil Dubord at a news conference on Thursday morning. "People who are using this drug at the street level thinking it can be used like their regular heroin that they would take on a regular basis, and all of a sudden the recipe on this counterfeit heroin isn't the same, that could result in death."

Last year, there were 470 fentanyl-related deaths in B.C., and so far this year, there are about 200.

Police said they were astounded by the business model demonstrated through the elaborate drug network. Sizeable profits could be made by selling the fentanyl as heroin. This was done by mixing the fentanyl with vinegar and brown food coloring to make it smell and appear like heroin. Police added the dealers also used special branding on the fake heroin.

"Put it all together and put it in a press. And on that press they would actually put their insignia, which was a fish," said Dubord.

Investigators recovered evidence of drug trafficking at the three residences, including nine firearms, two silencers, $1.5 million in cash, 4.5 kilograms of heroin, 12 kilograms of cocaine, and more than 4,500 oxycodone/oxytocin pills. They also found a S.W.A.T. Team Manual and an instruction book called "Kill or Get Killed."

Police say the level of violence theoretically associated with these crimes is startling.

“You carry large quantities of money on you at all times. And as a result, you have a reason to be carrying weapons, because you believe other people want that money. So, you learn how to fight with guns and you learn how to train yourself with firearms,“ added Dubord.

“You learn how to sell cocaine by the ton, is the book title. Those books train them in how to operate their drug operation, and you can see from the weapons including the silencers, they were prepared to kill for it.”

One city politician praised the police for their work on the file, which first came in as an “insignificant” tip.

"So we are very aware, very concerned. We're very happy to have our people on the street that know what they're looking for, and bring it to the top like this one was," said Delta Mayor Lois Jackson. "I believe you have saved many lives, thank you. Job well done."

Two Delta men, 35-year-old Scott Pipping of Surrey and 27-year-old Adam Summers, remain in custody, and face 21 trafficking-related charges, but police say more charges are expected. A 34-year-old Delta man and a 25-year-old Richmond man have also been arrested for trafficking in controlled substances and charges against them are pending. Several more arrests are anticipated.