Dehradun: Amid repeated disruptions in rescue work, there has been no breakthrough in finding the 25-35 people trapped inside the disaster-hit tunnel of the Tapovan project in Uttarakhand's Chamoli district on Thursday.

The rescue work was disrupted briefly following increase in flow of Dhauliganga river and technical snags in drilling machines. On the other hand, two more bodies were recovered on Thursday, taking the total to 36. Nearly 200 people have gone missing after the deluge in the region on Sunday morning.

"The rescue work inside the tunnel resumed in the evening after a brief interruption due to increase of flow in Dhauliganga river," said Navneet Bhullar, commandant of the SDRF, who is camping at the Tapovan site. However, no contact could be established with the trapped people inside so far.

Earlier, the rescue workers had started drilling the tunnel vertically downward. But within hours, the drilling work was also intermittently disrupted due to technical reasons. Few hours later, the flow of Dhauliganga started increasing which in turn disrupted the rescue work.

As the flows subsided, the rescue work again resumed in the evening, said Bhullar.

Ever since the excavation and digging work began inside the tunnel, the rescuers had been working on multi-pronged strategies in their desperate bid to open the blocked tunnel.

The rescuers have also used remote sensing technologies for geographical mapping of the tunnel. "We have used geographical mapping of the disaster-hit tunnel in the operation," said Ridhim Agarwal, DIG SDRF.

The rescue work had slowed down on Tuesday due to the presence of heavy silt inside the tunnel. DGP Ashok Kumar had said that all possibilities will be explored to save the lives of the trapped people.

After days of digging and excavation works, jawans of the army, ITBP, NDRF and SDRF, who are engaged in the rescue works, had managed to open a sizeable portion of the tunnel. But the presence of heavy silt and sludge inside the tunnel slowed down the rescue work, top government officials admitted. Rescuers have also consulted the NTPC officials to understand the complicated design of the tunnel.