NASCAR star Jimmie Johnson’s sister-in-law speaks out after parents’ death in ‘murder-suicide’

Muskogee police suspect Terry Janway shot her husband Jack and 11-year-old grandson Dalton before turning the gun on herself as officers arrived

NASCAR great Jimmie Johnson’s sister-in-law has spoken out after her parents and an 11-year-old relative were found dead in a suspected murder-suicide.

“Please tell me this isn’t really happening please god someone,” Marianne Janway wrote on Facebook after the bodies of Jack Janway, 69, his wife Terry Janway, 68, and their 11-year-old grandson Dalton Janway were found at the family’s home in Muskogee, Oklahoma, on Monday.

Marianne is the sister of Johnson’s wife Chandra Johnson, but it’s unclear if Dalton is her son.

Police suspect Terry Janway shot her husband and grandson before turning the gun on herself as officers arrived at the family home, according to a Muskogee Police Department statement.

Johnson, a seven-time NASCAR Cup Series champion, has pulled out of racing this weekend, while his teammates have offered their support.

“Sending love and prayers to my team mate Jimmie, Chandra and the whole Johnson family at this devastating time,” Johnson’s teammate and former Formula 1 champion Jenson Button tweeted.

Police in Muskogee received a 911 call from a woman at the family’s Suroya St address just after 9pm on Monday to report “a woman with a gun” before hanging up, according to a statement provided to the Muskogee Phoenix.

Officers arrived to find Jack Janway’s body lying in a hallway inside the door.

“Shortly after arriving officers heard another gunshot from further inside the house,” Muskogee Police spokeswoman Lynn Hamlin said in a statement.

Jack Janway and his grandson Dalton, 11, were killed in the murder-suicide, police say (Facebook)

They pulled Jack’s body out of the home and ordered anyone still inside the home to come out, according to the statement.

After back-up officers arrived, police searched the home and found Dalton and Terry’s bodies.

Ms Hamlin confirmed to the local news outlet that the deaths were being treated as a murder-suicide, and Terry Janway was considered the sole suspect.

Investigators have not identified a motive, Ms Hamlin added.

Jimmie and Chandra Johnson were married in 2004, and the couple have two daughters Genevieve and Lydia.

NASCAR driver Jimmie Johnson has withdrawn from racing this weekend (AP)

His Legacy Motor Club team said in a statement that Johnson’s No. 84 Carvana Chevrolet had been withdrawn from this weekend’s NASCAR Cup Series event in Chicago.

“The Johnson family has asked for privacy at this time and no further statements will be made,” the team added.

In a statement on Tuesday, NASCAR said: “We are 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.”

Tributes poured after Monday’s tragedy for Jack Janway had run the Janway Chiropractic & Acupuncture Clinic in Muskogee for decades.

“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 told Fox23.

“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.”

In 2014, Terry and Jack’s son Jordan Janway died in a skydiving accident near San Diego at the age of 27.

The veteran of more than 1,000 leaps collided with another skydiver and was unable to open his parachute, a medical examiner said at the time.

An obituary listed Dalton Janway as one of his nephews.