Rescue operations are currently ongoing at the Tapovan tunnel in Uttarakhand where at least thirty nine people are believed to be trapped.
Rescue teams are racing against time to clear the 2.5 km long tunnel and save those trapped after a glacier burst on Sunday triggering massive floods.
Rescue personnel said that more slush keeps coming back as they clear which is making difficult for the rescue team to enter the tunnel.
Uttarakhand Director General of Police (DGP) Ashok Kumar said on Tuesday that it is hoped the way will be cleared soonest.
The rescuers say they are also not sure in which part of the tunnel the workers are trapped or if they were together. At least 12 workers were rescued from a smaller tunnel in the same area on Sunday evening.
Reports say over 300 personnel of the Indo-Tibetan Border Police and 200 others from the army and disaster teams are involved in the operation.