Toronto police are warning the public after fentanyl patches were stolen from a car on Tuesday.
Approximately 20 prescription fentanyl patches were stolen in the Yonge Street and Finch Avenue area.
The police say the drug can be fatal when the patch is altered.
Fentanyl is an opiate used to relieve pain. The patches contain a clear gel that is time-released into the skin.
The Canadian Centre on Substance Abuse says the drug was involved in the deaths of at least 655 people in the last five years and fentanyl-involved deaths have significantly increased in British Columbia, Alberta, Quebec and Ontario.