Sgt. Lindsey Houghton of the Combined Forces Special Enforcement Unit said the bunker that housed 430 pot plants is believed to be linked to the Hells Angels motorcycle gang.
He said three men and a woman were arrested at the scene Saturday and released pending further investigation into the operation, which is believed to have existed for at least two years.
Police seized a loaded firearm in a bedroom, and a dozen pit-bull type dogs and chihuahuas found on the property were removed by a family member of one of the suspects.
Houghton said Tuesday that the grow-op, constructed from five shipping containers, was powered by natural gas diverted from a nearby pipeline.
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"The generator's muffler was disguised from view with an old manure spreader placed over top."
Contractors and heavy equipment operators, along with the local fire department, were on scene to help police dismantle the operation.
The complex operation had the potential to be extremely dangerous to both the public and emergency responders, Houghton said.
"The lengths that people constructing these types of grow-ops will go to are alarming. In spite of their efforts to hide from the police, however, we will continue to target organized crime groups and those people who are the most violent in our communities."
The agency shut down four similar grow-ops in Mission, B.C., last month that police believe were also linked to the Hells Angels.
A bunker grow-op in the Fraser Valley community was depicted as a horse paddock, Houghton said.