LUCKNOW: Excavators began drilling with heavy machinery on Tuesday to fix a wide steel pipe that will help pull out almost 40 Indian workers trapped inside a collapsed Himalayan highway tunnel that caved in two days ago in the north Indian state of Uttarakhand.

The tunnel, which was being built on a national highway that is part of a Hindu pilgrimage route, caved in around 5:30 a.m. on Sunday (2400 GMT on Saturday).

“We have been supplying food, water and oxygen to the trapped labourers and the officials are in continuous touch with all of them,” Devendra Singh Patwal, a disaster management official said.

Rescuers hopeful of reaching trapped labourers in collapsed Indian tunnel

Excavators have been removing debris for two days to carve out a path to reach the workers and had been awaiting delivery of a wide steel pipe which will be pushed into an opening of excavated debris to safely pull out the workers.

Patwal said it was not easy to ascertain the time required to pull out the workers.

A team of geologists from the state government and educational institutions had arrived to determine the cause of accident, he added.

The region is prone to landslides, earthquakes and floods and the incident follows events of land subsidence in the state that geologists, residents and officials have blamed on rapid construction in the mountains.

The work on the tunnel stretch commenced in 2018 and was initially intended to be completed by July 2022, which has now been delayed to May 2024, an Indian government statement said.

The Char Dham pilgrimage route is one of the most ambitious projects of Prime Minister Narendra Modi’s government.

It aims to connect four important Hindu pilgrimage sites of North India through 889 km (551 miles) of two-lane road being built at a cost of $1.5 billion.

But some work has been halted by local authorities after hundreds of houses were damaged by subsidence along the routes, including in Uttarakhand.