NorWest Community Health Centres and the Thunder Bay District Health Unit are warning residents about a contaminated drug supply in the city.

“A substance being sold as turquoise fentanyl came back as rat poison,” said NorWest Community Health Centre in a post to social media on Tuesday.It’s unclear how many people have been affected, but according to the health centre, multiple people have been hospitalized.

The organizations are encouraging drug users to test their supply at NorWest Community Health Centre’s Path 525 drug testing location on Simpson Street.