Jimmie Johnson's parents-in-law and 11-year-old nephew were reported dead late Monday night in a suspected murder-suicide.
Johnson, who was scheduled to compete in the NASCAR Chicago Street Race this weekend, withdrew from the event on Tuesday.
"The Johnson family has asked for privacy at this time and no further statements will be made," Legacy Motor Club, the team that Johnson co-owns, said in a statement.
Police found Terry, Jack and Dalton Janway dead inside a home in Muskogee, Okla. late Monday night. Muskogee police were called to the house around 9 p.m., finding a man's body lying inside the front door before hearing another gunshot from further inside the house, NBC affiliate KJRH reported.
The three bodies were found dead inside the home, leading the police to suspect that Terry Janway killed her husband, Jack, before killing her grandson, Dalton, and then herself.
Terry and Jack Janway were the parents of Johnson's wife, Chandra.
“We are saddened by the tragic deaths of members of Chandra Johnson’s family," NASCAR said in a statement. "The entire NASCAR family extends its deepest support and condolences during this difficult time to Chandra, Jimmie and the entire Johnson & Janway families.”
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Muskogee police are still investigating the incident.
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