After Biffle and family died, police think 'friends' stole from them

Less than a month after former NASCAR driver Greg Biffle and his family died in a plane crash last year, investigators say two of their "friends" conspired to break into the empty home and took cash, guns and financial information in an attempt to steal hundreds of thousands of dollars.More than 40 search warrants have been issued, authorities in North Carolina say, focusing on a married couple who allegedly knew Biffle and his wife Cristina. The suspects did "a lot of planning in an attempt to make a financial gain" off their deaths, Iredell County Sheriff Darren Campbell said. The Associated Press is not naming the pair because no arrests have been made.Biffle, his wife and his two children, along with three others, died in the Dec. 18 crash, which remains under investigation by the NTSB. Some survivors of those killed are suing the estates of Biffle and the pilot for millions of dollars.According to a search warrant affidavit, the husband being investigated met Biffle when the former driver used his private helicopter to deliver aid after Hurricane Helene. The woman attended a Christmas party at the Biffles' home in Mooresville, North Carolina, weeks before the crash.Authorities reported a break-in at the home Jan. 8, saying $30,000 in cash, two Glock handguns and NASCAR memorabilia were stolen. Search warrants were later executed at two sites, one near the Biffles' residence and another in a nearby county.A person seen on surveillance video, identified as a woman, appeared to be familiar with the large home's layout, including the locations of cameras, closets and a safe room, a detective wrote in a search warrant affidavit. The intruder spent nearly six hours inside the house the night of Jan. 7 into the following morning.Evidence showed a cellphone and multiple devices were active on the property during that time, according to the warrant. The only people allowed to be there would've been the administers of the estate, but they weren't present.Authorities say they linked the woman to someone who attended Biffle's celebration of life, and said license plate readers placed her husband's truck near the home that night.The warrants also describe alleged financial crimes. Investigators say that bank, Venmo and PayPal accounts tied to the Biffles were accessed online using personal information, with phone numbers and email addresses changed to gain control of funds. Money was then allegedly transferred to accounts not belonging to the family and used for purchases, according to the warrant.At least one fraudulent check tied to Biffle's business interests was cashed, and other attempts were made to access accounts. The activity occurred across multiple states. The sheriff would not say whether the same suspects in the break-in are being investigated for the financial crimes, saying the department is waiting for more evidence.Meanwhile, the plane crash sparked lawsuits against the estates of Biffle and the pilot Dennis Dutton, who was killed along with his son.On April 17, the estates of Dutton and his son sued Biffle's estate for at least $15 million each, alleging Biffle failed to properly maintain the plane and operated it in a defective condition. The claims include lost income and "pre-death pain and suffering."In February, Biffle's ex-wife, Nicole Biffle, filed a notice of claim against Dutton's estate on behalf of the couple's 14-year-old daughter's estate, seeking at least $10 million for wrongful death.