Police received the results of analysis by Health Canada and confirmed on Monday the drugs were 100 times more potent than fentanyl.
Guelph police’s Drug Enforcement Unit executed three search warrants around the city on March 19, and said they seized approximately 266 grams of suspected blue and purple fentanyl.
Police said it was the largest fentanyl seizure in their history.
Two men and a woman were arrested and charged with several drug, weapon and stolen property offences.
According to police, testing by Health Canada showed that approximately 260 grams of the drugs tested as carfentanil.
A police spokesperson said the results do not change the street value of the drugs seized and won’t impact the charges that have already been laid.
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