Quebec provincial police arrested two dozen people and dismantled marijuana grow operations at 40 locations across the province Wednesday.
The operation, led by provincial police force the Surete du Quebec, began at 6 a.m. in Montreal, Gatineau, Quebec City and other regions.
"The Surete du Quebec and its partners dismantled about 40 indoor cannabis greenhouses under a comprehensive eradication operation," the SQ said in a statement.
"So far the eradication operation has led to 22 arrests and the seizure of 13,000 cannabis plants. More arrests are expected."
Officers also seized firearms and more than 300 lamps that were used to grow marijuana crops.
Nearly 500 provincial and local police officers were involved in the operation.
Hydro-Quebec officials also visited some sites where the power supply had been siphoned, said SQ spokesman Gino Pare.
The raids were expected to continue throughout the day.
"Depending on the scale of the crops that are found, it could take hours," Pare said.