The operation to rescue 41 workers trapped inside a tunnel in India’s Uttarakhand state has resumed after hitting a snag, officials say.
They hope to free the workers in the next 10-12 hours if things go to plan.
The workers have been inside the tunnel since 12 November after a part of it caved in due to a landslide.
On Wednesday, the operation to rescue them hit a snag after a drilling machine encountered a steel structure it could not cut through.
Gas-cutters were then used to slice through the obstacle, which delayed the work by around six hours. Rescuers had drilled through three-quarters of the debris trapping the workers in and hopes were high that the workers could be brought out by Thursday morning.
“If everything goes to plan, and there are no impediments, we should complete the rescue by tonight,” Atul Karwal, director general of the National Disaster Response Force (NDRF), told BBC Hindi.
Mr Karwal added that the authorities were prepared to deal with any obstacles that might come in their way.
“We will get these men out,” he said.
Officials established contact with the trapped men hours after the collapse. They have been supplying them with oxygen, dry snacks and water through a pipeline that was laid for supplying water to the tunnel for construction work.
They have also been communicating with them regularly and giving updates on their health.
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Friends and relatives of the workers are waiting anxiously and have been asking why it is taking so long to get the men out. Earlier this week, some of them were able to get a glimpse of their loved ones through an endoscopic camera inserted inside the tunnel.
On Thursday, Mr Karwal said that Uttarakhand’s Chief Minister Pushkar Singh Dhami spoke to the workers in the morning and they seemed to be in good spirits.
“Even they feel they will be rescued soon,” he said.
Authorities have been working to send multiple pipes of differing widths through the estimated 60m (197ft) debris wall to create a micro-tunnel through which the workers can be brought out.
But the operation has encountered several delays and obstacles due to loose soil, hard rock and falling debris.
An American-made auger drill was flown in from across the country to drill through the debris, after excavators failed to clear the thick mound of soil and rock. The powerful tool has a spiral shaft at the end that spins to push soil and stones away and make its way into the ground.
Once the final rescue pipe reaches the workers, a doctor will be sent ahead to check on their condition.
Ambulances have been kept on standby outside the tunnel. Officials say the aim is to pull the workers out to safety and shift them to the nearby hospital as quickly as possible.
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