Oxygen is being pumped into the collapsed section of the tunnel, which is part of the Char Dham all-weather road project, through a water pipe so that the trapped labourers do not have difficulty breathing, Yaduvanshi said.
The rescue operation has been going on for the past 12 hours but without any breakthrough so far.
However, those trapped inside have sent out signals that indicate they are safe, an official at the site said.
“We are removing the muck to measure how deep the point where they are trapped is. It does not seem too long. We hope to reach them soon. However, there are indications that they are safe as they appear to have released some water through an outlet,” Rajesh Panwar, the Navyuga Construction Company project manager, said.
About 160 rescuers are trying to reach the trapped labourers with the help of drilling equipment and excavators, the District Emergency Operation Centre said. Some more equipment such as a vertical drilling machine are about to reach the site to assist the rescue efforts.
Border Roads Organisation and Indo-Tibetan Border Police teams led by Commanding Officer Naman Narula and Assistant Commandant Jadhav Vaibhav were roped in later to assist the rescue efforts, the officials said.
Uttarkashi District Magistrate Abhishek Ruhela, National Highways Authority of India Chief General Manager Vishal Gupta and NDRF Second-in-Command Ravishankar Badhani are on the spot to supervise the search and rescue operation.
Chief Minister Pushkar Singh Dhami spoke to Ruhela for an update on the situation and asked him to speed up the rescue operation.