Police in Muskogee, Oklahoma, are investigating the shooting deaths of three relatives of NASCAR driver Jimmie Johnson. Muskogee police spokesperson Lynn Hamlin says the bodies of Jack Janway; his wife, Terry Janway; and their 11-year-old grandson, Dalton Janway, were discovered Monday at a home in Muskogee. Hamlin confirmed the three are the parents and nephew of Johnson’s wife, Chandra Janway. Hamlin says investigators believe Terry Janway shot and killed her husband and grandson before shooting herself. Johnson’s race team has announced it is withdrawing his No. 84 Carvana Chevrolet from this weekend’s NASCAR Cup Series event in Chicago.