Boone County sheriff’s deputies say a Columbia-area murder suspect is behind bars this morning in southwest Iowa. The sheriff’s department says 36-year-old Mark Achterberg has been captured in Creston, which is 80 miles east of Omaha. Achterberg is charged with killing 32-year-old Justin Stidham on Monday, at Stidham’s home on North Kent drive. A Boone County …