Sgt. Richard Barrett with the Colby Police Department reports that officers have taken several reports of counterfeit $20.00 bills being passed in Colby. The counterfeit bills all have the same serial number D63791708B. They are older 1985 series bills so they do not have the new security markings. The borders of the face of the bills are off or nonexistent. Please be aware when taking US currency so no business becomes a victim.