MANKATO-September 17-(KMKO)-An undercover drug bust has led to felony charges against a Mankato man. Agents from the Minnesota River Valley Drug Task Force conducted a controlled buy of marijuana using a confidential informant last Tuesday. The informant bought just over six grams of pot from 18-year-old Payton Michael Gilbertson in the parking lot of Smokes 4 Less. Gilbertson has been charged with one count of fifth degree sale of marijuana. Payton has two previous convictions for marijuana sales on his record, as well as one count of possession of a dangerous weapon on school property.