46-year-old Michael Donovan Avin of Darlington, SC was arrested after threatening to bomb Darlington Raceway, the track that NASCAR is racing on this Sunday for the Cup series. According to the Darlington Sheriff's department, on April 27th, Avin called the Darlington Raceway and left threatening messages describing a "possible explosive device." Investigators also allege that Avin indicated in a letter written to another location in Darlington County that he had access to 125 tons of bomb making materials. Avin was arrested and charged with possession, threatened or attempted use of a weapon of mass destruction for an act of terrorism. The case still remains under investigation.