Calgary police say thanks to a tip from the public they have made their largest ever seizure of the dangerous and powerful opioid fentanyl.

Acting Insp. Mark Hatchette said officers found 35,321 fentanyl pills last Friday during a drug bust at a rented home in an affluent neighbourhood.

"This is the largest seizure of fentanyl in Calgary history," Hatchette said Thursday at a news conference.

"It is definitely not the end of what we consider to be a new-style drug that is trying to take hold in the city. We see it in our overdoses and other types of issues surrounding social disorder based on drug use and addiction."

Illegal fentanyl, which can be up to 40 times stronger than heroin, has been linked to hundreds of deaths across Canada.

Investigators also seized shotguns, rifles, a handgun, a crossbow and other drugs including cocaine, methamphetamine and heroin.

Police also found lots of ammunition and sets of body armour.

Hatchette said police believe the fentanyl pills were brought in to Calgary from another area.

David Pratico of Calgary has been charged with drug and weapons-related offences, including the production of crack cocaine.