The devastating landslide had brought down the green trees and debris, boulders and breached the highway bringing all traffic on the national highway to a standstill yesterday for 12 hours.
NHAI had restored it yesterday for single way small vehicles, but the entire road stretch at the same site subsided today.
The landslide caused the collapse of the entire hill from the upper side, severely damaging the highway stretch that has now raised questions about the quality of construction of the highway by the NHAI contractors for the third time.
Earlier, the four lane stretch collapsed near Solan town in 2022 that is yet to be restored. 
The LMVs are diverted via Kasauli to Parwanoo to Chandigarh from Dharampur and big vehicles from Kumarhatti via Nahan to Chandigarh till the highway is restored, said the HP police.
According to the commuters, the damage to the highway was so massive that there is no trek left for even walking from one side to the other as the entire hill collapsed and breached the 50m long stretch of the highway the same site.
The National Highway Authority of India (NHAI), responsible for maintaining the highway, deployed machinery, but the extent of the damage is huge and would take time to the restore the highway.