DULUTH (AP) — Police in the Duluth area say three people recently have died of drug overdoses.

Police in Duluth and nearby Hermantown said Monday that the three died of overdosing on opioids in the past 48 hours.

Doctors prescribe opioids for a range of ailments, from post-surgical pain to arthritis and migraines.

In a news release, police say they are concerned about opioid users and warn that the content and purity of the drugs is often unknown and can lead to a fatal overdose.

Police are investigating the deaths. No other details were released.