CNN  —  Prosecutors are fighting to keep a Virginia man behind bars after they say investigators found what could be the largest number of “finished explosive devices” in FBI history at his 20-acre home near Norfolk. The man, Brad Spafford, was arrested earlier this month on one charge of possessing an illegal unregistered short-barrel rifle. During the arrest, the FBI – including bomb technicians – executed a search warrant on his property and found a stockpile of more than 150 apparent pipe