Prime Minister Narendra Modi’s principal secretary P K Mishra on Monday visited Uttarakhand’s Silkyara tunnel, where 41 labourers have been stranded for the last 15 days, ANI reported.

He took stock of the rescue mission and also communicated with the workers trapped there. Follow LIVE updates here.

Mishra also spoke with the families of the trapped workers and also took a report of the food items being sent to the workers.

The mission to rescue the trapped workers entered its 16th day on Monday. Officials are currently carrying the vertical drilling to rescue the 41 workers in the collapsed section of the Uttarkashi tunnel.

The vertical drilling of the hill in Silkyara commenced on Sunday afternoon, with around 110 meters of the hill to be dug out for the rescue of the trapped workers. In a fast-paced operation, the machine has already drilled 30 meters of the hill, with over 80 meters still left.

On Monday, former director general of Border Roads Organisation Harpal Singh said that preparations are also underway to start horizontal drilling inside the main tunnel manually, according to PTI. Rescuers need to manually dig 10 to 12 metres through the rubble after the auger machine broke down.

“Frames of 800 mm diameter pipes have been prepared. We will move ahead by half a metre to one metre gradually,” he told the news agency. “If all goes well and no obstacles are encountered a 10-metre stretch can be covered in 24-36 hours.”

The Centre and state government have designed a total of six rescue plans for the Uttarkashi mission. If vertical drilling fails, agencies will resort to sideways drilling and drift technology to rescue the trapped men.

While no timeframe has been given on when the final phase of the rescue mission will be complete, the pace of the vertical drill remains fast. It is speculated that the mission will be over in the next 24-36 hours.

Further, a team of doctors and a hospital facility with 41 beds have been prepared near the tunnel collapse site to reduce any margin of error when it comes to saving the lives of the trapped workers.