Jimmie Johnson will not race this weekend in NASCAR's Cup Series street race in Chicago following the deaths of his wife's parents in Oklahoma.

Police in Muskogee, Oklahoma, told TMZ that Jack and Terry Janway and an 11-year-old boy were found dead in their home Monday night. Police said they received a 911 call from a woman who reported someone with a gun before hanging up.

All three died from gunshot wounds, police told TMZ. The circumstances of their deaths remain under investigation.

NASCAR this week is preparing for its first foray into street course racing. Johnson, a seven-time Cup Series champion, is racing on a part-time basis this year as co-owner of Legacy Motor Club. He drives the No. 84 Carvana Chevrolet.

"The Johnson family has asked for privacy at this time and no further statements will be made," Legacy Motor Club said in a tweet.

"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."