Stratford and Perth officials are expressing alarm after four people died of suspected fentanyl overdoses in the last month.

"That's concerning because it seems to be an increase in activity," says Miriam Klassen, the medical officer of health for the Perth District Health Unit.

She says in the second quarter of 2018, there were no opioid-related deaths in the area.

A strategy group has been formed, Klassen says, and includes police, fire officials, school boards, addiction services and others.

The hope is that this group can monitor local activity and get information out to the public.

"What we're hearing is that methamphetamine and heroin is being mixed with fentanyl," Klassen says.

"We want to get this information out to the community so that the community can be safe and understand."