The activists led by Congress MLA Jasbir Singh Dimpa blocked at the flow of traffic on the GT road for about two hours and asked the state government to act against people linked with drug mafia.
During the protest, Congress members set ablaze the effigy of Punjab government and Revenue Minister Bikram Singh Majithia.
He accused Majithia of having links with drug mafia.
Dimpa attacked the state government for its alleged involvement in black marketing of sand, gravel, food grains and synthetic drugs.
The chief minister should recommend a CBI probe into drug racket, Dimpa said.
The Congress legislator also accused the state police of giving clean chit to people involved in illegal activities.