Three weeks after Greg Biffle, his wife and their two young children died in a plane crash, sheriff’s deputies were dispatched to the estate where the retired NASCAR driver and his family lived in Mooresville, North Carolina.

Thus began an investigation into an alleged break-in and theft reported Jan. 8, and Iredell County Sheriff Dan Campbell told the Associated Press $30,000 in cash was stolen.

The investigation continues at the same time “A Gathering in Remembrance” is scheduled to be held Friday, Jan. 16, to honor the lives lost in the Dec. 18 plane crash.

In addition to the death of Biffle, his wife Cristina and his two children — daughter Emma and son Ryder — three other people died in the crash of the Cessna Citation. According to WTVD in Durham, North Carolina, the plane hit the ground short of the runway at Statesville Regional Airport and then burst into flames.

As the grieving continues, the Iredell County Sheriff’s Office now is tasked to determine what happened during the apparent burglary of the Biffles’ home.

Campbell told the Associated Press that no arrests have been made and that investigators think someone entered a safe in the home. In addition to $30,000 missing, some guns and memorabilia also are gone, according to the Associated Press report.

Biffle, who won 19 races on the Cup Series, retired from full-time competition in 2016.

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