SIOUX FALLS, S.D. (MITCHELLNOW) Authorities are investigating two stabbings that occurred over the weekend at the South Dakota State Penitentiary. The Attorney General’s office says both the Division of Criminal Investigation and the Department of Corrections Inspector General are handling the cases. The incidents remain under investigation. The violence comes as lawmakers get ready to vote next week on a proposal to build a new men’s prison in northeast Sioux Falls, replacing the 144-year-old facility.