Steve Simpson, sheriff of Loudoun County, Virginia, sent 22 deputies equipped with food and water to last seven days. Their 14-car caravan, including four all-terrain vehicles, was on the road just three hours when they were told to turn back. The reason, Simpson told CNN: A Louisiana state police official told them not to come. " I said, "What if we just show up?' He says, 'You probably won't get in.'" Simpson said he later learned a dispute over whether state or federal authorities would command the law enforcement effort was being ironed out that night. But no one ever got back to him with the all-clear.