One month after Jimmie Johnson's wife's parents died in an apparent murder-suicide, the NASCAR champion has taken to social media.

Friday's statement is his first since the late-June tragedy in Muskogee, Okla.

Dr. Jack Janway, 69, Terry "Lynn" Janway, 68, and Dalton Janway, 11, died at the Janway family home on June 26. Police said they believed Terry Janway killed her husband and her grandson before turning a gun on herself.

Johnson's wife is Chandra Janway, and the couple have been married since 2004.

Related: NASCAR Driver Jimmie Johnson's In-Laws Killed

"Our family is devastated by the profound loss of Lynn, Jack and Dalton Janway," Jimmie Johnson writes on social media.

"We have been humbled by the outpouring of love and support during this unthinkably sad time and remain grateful for all your love and compassion."

Police have not shared any updates about the case or investigation. It began just after 9PM, when police received a call from a woman in the home who said there was a disturbance and someone had a gun, before hanging up.

When police arrived, they immediately saw someone lying motionless in the hallway, and upon entering, heard an additional gunshot. A motive is not clear. The Janways had previously lost a son in a skydiving accident.

NASCAR issued a statement the next day:

"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."

Chandra Janway Johnson is a former model, and she's not very active on social media. The couple have two kids, 9-year-old Lydia and 12-year-old Genevieve.

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