Two lorries and a van were seized and 16 vehicles ordered off the roads on Teeside during a police clampdown.
Operation Luxembourg followed concern over illegal dumping in the Newtown and Wrensfield areas of Stockton.
Cleveland Police joined forces with Stockton Council, the Environment Agency and Customs and Excise for the six-hour operation on Monday.
A lorry carrying scrap was impounded for having no operator's licence, and an uninsured lorry and a van seized.
In one of the cases officers discovered the driver had never passed his test.
Prohibition notices were issued on 16 vehicles, which were ordered off the road until defects were fixed.
A Cleveland Police spokesman described the operation as successful and said that further clampdowns would be carried out in the future.