WILSON, N.C. (AP) – Details emerging in the theft of nearly $5 million in gold bars on an interstate highway reveal why authorities have been suspicious from the beginning that the heist was carefully planned.

The robbers pulled up almost immediately after the drivers made an unscheduled stop on a dark stretch of highway in North Carolina, according to a warrant. The sheriff says the thieves even had orange traffic cones to put in place while they unloaded the gold.

Wilson County Sheriff Calvin Woodard said at a news conference Wednesday that the case is suspicious and he believes the shipment was targeted by thieves who had a plan.

Authorities say $4.8 million in gold bars was stolen from the truck Sunday night along Interstate 95 east of Raleigh.