Sheriff’s deputies in North Carolina are investigating an alleged break-in and theft at the home of retired NASCAR driver Greg Biffle, officials said.

The Iredell County Sheriff’s Office incident report says the alleged burglary and forcible entry at the Biffle home in Mooresville was reported Jan. 8.

Sheriff Darren Campbell said Wednesday that investigators believe someone entered a safe in the home. Campbell said the theft included $30,000 in cash and a backpack identified in the incident report as stolen, and that some guns and memorabilia also were taken.

Campbell said no arrests have been made and that no one else was in the home at the time of the alleged crimes. The incident report said the home was last known secure the afternoon of Jan. 7.

“We’re working the case. We are waiting on some digital evidence,” Campbell said, adding that interviews also were being conducted.

The alleged burglary comes weeks after a business jet crash in December killed Biffle and seven others. Federal investigators said a Cessna C550 erupted into a large fire when it hit the ground short of the runway and that everyone on board died.

Investigators said the jet carrying Biffle, his wife and two children, and three others crashed Dec. 18 while trying to return to an airport in Statesville—about 45 miles (72 kilometers) north of Charlotte—minutes after taking off from there. No cause of the crash has been released.

The report said Biffle was one of three people on board with a pilot’s license. It also said investigators told reporters during the crash’s immediate aftermath that they did not know who was the lead pilot on the flight.

A public memorial service for Biffle, who won 19 NASCAR Cup Series races over his career, and the six others killed is scheduled for Friday morning at a Charlotte arena.