A North Mankato woman was arrested after a search warrant was executed Thursday by the Minnesota River Valley Drug Task Force. Authorities say 51-year-old Roberta Brown was charged with fifth-degree sales of a controlled substance and being a felon in possession of a firearm. Authorities say Brown was arrested for the same offenses in November. The Minnesota River Valley Drug Task Force located 235 grams of synthetic cannabinoids and a loaded 22 pistol during the execution of the search warrant in the 1700 block of Northway Drive in North Mankato.