MANKATO, Minn. (AP) — Police say four people have been arrested on drug charges in connection with an investigation into a synthetic drug that may have killed two people in Mankato.

Police believe a synthetic drug called "2-C" was sold in blue packages with gold or silver crowns on it.

One package with that description was found last week at a house where a 22-year-old man died, and a second package was found at a house owned by the mother of a 17-year-old girl who died this week.

Police haven't confirmed that the drug caused the deaths, but they suspect it was a factor.

Police announced the arrests Thursday. The suspects range in age from 15 to 30. Police say they are being charged with controlled substance violations.