$13M Carfentanyl seizure in Pickering 'the biggest' in Canada, Durham police say

An Oshawa man previously arrested on more than 330 firearm charges is now facing an additional drug chargeafter police found largeamounts of a deadly opioid at a Pickeringresidence late September.

Durham Regional Police say they discovered asuspicioussubstance while responding to a carbon monoxide alarm in a residentialPickeringneighbourhood on Sep. 20.

• Oshawa man faces 337 charges after 33 guns found in Pickering home

After obtaining a warrant, Durham police, along with the Ontario Provincial Police's clandestine lab unit, found 33 guns and 53 kilograms of an unknown substance in the basement of the home.

Lab results from Health Canada have now identified 42 kilograms of that substanceas Carfentanyl.

It's the biggestCarfentanylseizurein Canada,Const.GeorgeTudostold CBC Toronto.

"Carfentanil or carfentanyl is a synthetic opioid similar to fentanyl but 100 times more potent," Durham Regional Police said in a news release.

The total seizure equals 420,000 doses of carfentanyl. That carries astreet value estimated at $13 million dollars, police say.

"This is a very deadly drug. It's not only dangerous for users but also for any first responders that are helping people that are overdosing or anyone that comes in contact with this drug," Tudos said. "A very small amount of this drug can be lethal."

A 33-year-old man is in custody in relation to the charges.