Section 20(3) in The Motor Vehicles (Driving) Regulations, 2017
(3)No driver shall stop or park the vehicle within a tunnel unless absolutely unavoidable and, in such situation, switch on the hazard warning lights of the vehicle and also place reflective traffic warning triangles as specified in clause (c) of sub-rule (4) of rule 138 of the Central Motor Vehicles Rules, 1989, at a distance of twenty meters each from the vehicle in the front of, and behind, the vehicle.
