On November 13, Indian rescue forces used heavy excavators to clear the rubble to reach 40 workers trapped after the tunnel collapsed.
Uttarakhand state officials said there were some signs that the trapped workers were alive. Rescuers were pumping oxygen into the blocked tunnel and trying to bring food in through water pipes.
Images released by government rescue teams showed large piles of concrete blocking the wide tunnel, but a rescue official said excavators had removed some of the rubble.
The tunnel collapse occurred early on the morning of November 12, when two groups of construction workers were changing shifts. According to local disaster response agency representative Durgesh Rathodi, about 200m of the tunnel collapsed, trapping about 40 workers inside.
The construction of the 4.5-km tunnel is part of the Indian government's Char Dham road project to improve connectivity to the country's largest Hindu shrines as well as the border area with China.
According to Tin Tuc newspaper