Portland police responded to five overdoses Sunday involving what they suspect is contaminated heroin.

The police department said the heroin likely contains a type of veterinary animal tranquilizer, which if injected can cause necrotic wounds, serious injury or death.

Police reported no fatalities Sunday. While the tranquilizer does not respond to Narcan, an opioid antidote, officers were able to use it to reverse the effects of the five reported heroin overdoses.

Police ask anyone with information to call (207) 874-8575.