SPRINGFIELD, Ill. (AP) — Four family members of a Republican running for governor in Illinois were killed in a Montana helicopter crash, his campaign said Thursday.

Killed in the crash Wednesday were the son and daughter-in-law of former state Sen. Darren Bailey, a Republican who lost the 2022 gubernatorial election in Illinois and is seeking his party’s nomination again in next year’s race.

Bailey’s son, Zachary, his wife, Kelsey, and their two young children, Vada Rose, 12, and Samuel, 7, died in the crash, his campaign said in a statement. The couple’s third child was not on the helicopter.

“Darren and Cindy are heartbroken by this unimaginable loss. They are finding comfort in their faith, their family, and the prayers of so many who love and care for them,” the statement said.

The National Transportation Safety Board said Thursday that it was investigating a helicopter crash in eastern Montana near the town of Ekalaka. The sheriff’s office in Carter County said the helicopter went down southwest of the town early Wednesday evening.

Bailey, from the southern Illinois town of Xenia, announced this year that he is seeking the GOP’s nominee for governor in 2026. He lost to Gov. JB Pritzker in 2022 after serving single, two-year terms in both the Illinois House and Senate.

He unsuccessfully challenged five-term incumbent Republican U.S. Rep. Mike Bost in last year’s primary race for a district that covers much of the bottom one-third of Illinois.

Illinois GOP Chair Kathy Salvi said in a statement that the party is grieving the tragic loss. “Please join us in keeping the Bailey family in our thoughts and prayers during this unimaginable time,” the statement said.