NASCAR driver Jimmie Johnson's in-laws, nephew found dead in Oklahoma

June 27 (UPI) -- The mother-in-law of NASCAR driver Jimmie Johnson is suspected of shooting her husband and grandson dead before killing herself, reports said Tuesday.

Terry Janway, the 68-year-old mother of Johnson's wife, Chandra Janway, is believed to have shot her husband Jack Janway, 69, and their 11-year-old grandson Dalton at their home in Muskogee, Okla., on Monday night, KOKI-TV reported.

Police told KOKI-TV that Terry Janway called 911 around 9 p.m. on Monday to report a disturbance and someone with a gun.

Responding officers found the body of one of the family members in the hallway inside the front door then heard gunshots from inside the house.

Police pulled the initial body out of the home then searched inside and found two more people dead.

Lynn Hamlin, the spokesperson for the police department, described Terry Janway as the "suspect" in the shooting in remarks to NBC News.

The motive for the shooting remains unclear, as well as further details about the 911 call, but the incident is being called a possible murder-suicide by news outlets.

"It was traumatizing to find out that a long-standing family who had made so many contributions to our community were involved in this type of incident. It was even more bone-chilling to find out there was a child involved," said Muskogee Mayor Marlon Coleman.

"I knew Dr. Janway. Dr. Janway has worked on me, we've been acquaintances for a very, very long time since I've been in Muskogee. Just knowing that it was him and his family took a different toll on me."

Johnson's team withdrew from a race in Chicago scheduled for Sunday and said in a statement that his family has asked for privacy.

"LEGACY MOTOR CLUB has elected to withdraw the No. 84 Carvana Chevrolet from this weekend's NASCAR Cup Series event in Chicago," the statement reads. "The Johnson family has asked for privacy at this time and no further statements will be made."

NASCAR also issued a statement Tuesday and said the stock car racing association is "saddened" by the "tragic deaths of members of Chandra Johnson's family."

"The entire NASCAR family extends its deepest support and condolences during this difficult time to Chandra, Jimmie and the entire Johnson & Janway families," the statement reads.

Jimmie Johnson has won seven NASCAR Cup Series championships, leaving him tied with Richard Petty and Dale Earnhardt for the most of all time. He has competed in at least 687 NASCAR Cup Series races and another 93 races in the NASCAR Xfinity Series.

If you or someone you know is suicidal, call the National Suicide Prevention Lifeline at 988.