Uttarkashi (Uttarakhand) | The operation to rescue 40 labourers stuck in the partially-collapsed Silkyara tunnel in this Uttarakhand district has been suspended since Friday, when a US-made auger machine deployed to drill and push in pipes developed a snag.

Another high-performance drilling machine airlifted from Indore in Madhya Pradesh has already landed at the Jolly Grant airport in Dehradun and is being transported by road to Silkyara where it will be unloaded and assembled before being deployed for drilling, officials on the spot said.

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 a 60-metre area inside the tunnel.

Around 2.45 pm on Friday, during the positioning of the fifth pipe, a loud cracking sound was heard in the tunnel after which the rescue operation was suspended, a statement issued by the NHIDCL late on Friday night said.

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.

PMO Deputy Secretary Mangesh Ghildiyal is coming to Silkyara for an on-the-spot review of the rescue operations, officials said.

The tunnel is central government project being constructed under the National Highways & Infrastructure Development Corporation Limited.