Indian military engineers prepared to dig by hand on Monday to try to reach 41 workers trapped for 16 days in a collapsed road tunnel in northern India, after rescue operations suffered multiple setbacks.

Only nine meters remained to drill through the rubble to insert the final section of the 57 meter long steel tube, wide enough for a man to pass through, and allowing workers to evacuate.

But the drilling encountered tangled metal rods and construction vehicles blocking the road, damaging the machine beyond repair.

Indian troops on Monday will try to clear rocks and debris from the remaining nine meters as temperatures drop in the remote mountainous region of the Himalayan state of Uttarakhand.

“Personnel of the Indian army’s engineering battalion, as well as other rescuers are preparing” for the operation, a senior local official, Abhishek Ruhela, told AFP on Monday.

In freezing conditions, engineers would use hand drills to clear the route, a difficult task in the narrow channel, which is wide enough for a person to pass through.

Since the tunnel collapsed on November 12, rescue efforts have been complicated and slowed by falling debris and successive failures in drills, critical machines for rescuing workers.

These people have survived for two weeks thanks to the delivery of air, food, water and electricity through a channel equipped with an endoscopic camera. These cameras allowed their families to see them last week, for the first time since the tunnel collapsed.