ELLSWORTH, S.D. (MITCHELLNOW) A 24-year-old airman stationed at Ellsworth Air Force Base is facing a federal murder charge.  The Pennington County Sheriff’s Office said Quinterius Chappelle is accused in the death of 21-year-old Sahela Sangrait who was last seen in August. Her body was found by a hiker near Hill City earlier this month. Because it’s believed she was killed on the base, the U.S. Attorney’s Office has jurisdiction and will be prosecuting the case. For more crime stories from MitchellNow.com, click here.