Their voices are getting weaker, their strength seemingly dimming, those keeping vigil outside the Silkyara tunnel here said on Saturday after speaking to their relatives trapped inside for seven days – and counting.

The under-construction tunnel on the Char Dham route collapsed on Sunday morning with 40 labourers inside it. As the hours tick by, the desperation of families waiting outside is mounting. That rescue operations have been suspended since Friday when a US-made auger machine deployed to drill and push in pipes through the rubble to prepare an escape passage for the workers developed a snag has exacerbated the anxiety.

The health condition of the men counting the hours inside the dark tunnel is worsening and his family back home getting increasingly panicky, said Haridwar Sharma, whose younger brother Sushil is among those inside the tunnel.

"All we are getting are assurances from authorities that the trapped labourers will be rescued. It has been nearly a week," Sharma, who is from Bihar's Rohtas district, told PTI.

“There is no work going on inside the tunnel. Neither the company nor the government is doing anything. The company says a machine is on the way,” he added tearfully.

Among those waiting is the family of Gabbar Singh Negi. His two brothers, Maharaj Singh and Prem Singh, and son Akash Singh have been camping outside, desperate for any sliver of news that comes their way. The family belongs to Kotdwar in the state.

Maharaj said he spoke to Gabbar through a pipe used for supplying oxygen and his voice sounded very feeble. "I could not talk to my brother. His voice sounded very weak. He was hardly audible. Rescue work in the tunnel has come to a halt. Those trapped are also short of food and water. We have come to the end of our patience. What more can I say?" Maharaj told PTI.

Their brother Prem said the trapped workers are beginning to lose hope. "Gabbar said he is alright but his voice is feebler now. They are getting light edibles like chana, kheer and badam. How long can they sustain on this? Work has been stalled for 30-32 hours inside the tunnel," Prem said.

"India has gone digital. They talk about the success of India's Chandrayan mission but they cannot evacuate our people trapped for around a week." Gabbar’s son Akash Singh echoed his uncles.

"His voice was low. Though he said he was alright so that we don't get worried. His low voice said it all. No work is going on inside the tunnel. There are no engineers inside, only people who send food and water through a pipe to the trapped workers from time to time are there," Akash said.

As anxiety levels mount, officials at the spot said a high performance drilling machine airlifted from Indore has landed at Dehradun’s Jollygrant airport here and being taken by road to Silkyara where it will be unloaded and assembled before being deployed for drilling. By the time the operation was halted on Friday afternoon, the heavy duty auger machine had drilled up to 24 metres through the rubble spread over around a 60 metre area inside the tunnel. Around 2.45 pm on Friday, during the positioning of a fifth pipe, a big cracking sound was heard in the tunnel upon which rescue operation was suspended immediately, a statement from the National Highways & Infrastructure Development Corporation (NHIDCL), the company tasked with the construction of the tunnel, said in a statement on Friday night. The sound created panic among the rescue team. An expert involved with the project warned about the possibility of further collapse in the vicinity. Subsequently, the pipe pushing activity was stopped.

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