Hundreds of trucks were stopped in Douglas County, Georgia on I-20. They were being inspected for radiation. This effort is part of an operation called VIPER (Visual Intermodal Protection and Response).

The only news coverage this story got was by a local Atlanta TV station:

However, federal sources told Channel 2 investigative reporter Mark Winne the inspections are part of a counter-terrorism operation.

News Chopper 2 showed screening devices, dogs and a large drive-through bomb detection machine in use along the eastbound interstate near Lee Road. Counter-Terror Operation Stops Trucks On I-20, WSBTV, September 29, 2010

They had a video [watch] of the incident that shows just how big the operation was.