Late NASCAR star Greg Biffle‘s wife, Cristina, sent her mom an alarming message minutes before they died in a plane crash.

Cristina Biffle texted her mother, “We’re in trouble,” according to PEOPLE.

Greg’s mother-in-law, Cathy Grossu, told the outlet that’s all she heard from her daughter before the plane crash … and she says the family is “devastated” and “brokenhearted.”

As we reported … Thursday’s fiery crash in North Carolina claimed seven lives … Greg, Cristina, and his two kids … plus Dennis Dutton, his son, Jack, and Craig Wadsworth.

The private jet, a Cessna C550, was registered to a company owned by Biffle … and it crash-landed near a runway 26 minutes after taking off from Statesville Regional Airport.

The flight was originally scheduled to travel to Florida, but the plane seemed to turn back towards the airport just minutes into the flight.

It’s unclear what caused the crash … the FAA is investigating.