Lorries running in day time

There's a rule in the city or urban areas that no heavy vehicles should come or run in the city premises from 6 am to 10 pm. But still there were many lorries which were carrying sands and other materials running in the city in the day time. To escape from cops , they take a short cut to the main road and create a hell of traffic even in the peak hours.
   If they were running in the main road, they are getting caught by the cops because the police aware that a single lorry can jam the entire road. So these lorry drivers taking short routes to avoid them. Cops should track those guys who were involved in those activities and strict action should be taken against them .