Forty-one construction workers trapped in a collapsed highway tunnel in India for 11 days could be rescued later on Thursday.
Rescuers are metres away from the group after nearly two weeks of digging and delays in Uttarakhand, a state in northern India crossed by the Himalayas.
The workers became trapped on November 12, when a landslide caused part of the 2.8-mile tunnel they were building to collapse about 200 meters from the entrance.
Rescuers plan to insert and weld together pipes that will be the trapped workers' route to freedom, once they finish excavating 13 metres of dirt and debris.
Drilling of the final stretch has resumed following a six-hour delay, after blades on the drilling machine were damaged by a metal object in the debris.
"The machine has started operating again in full swing. So we are hopeful that it will finish early," said Atul Karwal, chief of the state-run National Disaster Response Force.
"We should be able to rescue them in today's date," he told reporters at the site.
It took six hours to remove the metal pipes obstructing the drilling, said Bhaskar Khulbe, another official.
Pushkar Singh Dhami, Uttarakhand state's top elected official, visited the site on Thursday and spoke to some of the trapped workers through walkies-talkies, Mr Karwal said.
The drilling has made it through 44 meters out of around the 57 metres needed, Harpal Singh, a manager of another tunnel project who is helping with the rescue, told the Press Trust of India news agency.
Rescuers restarted drilling horizontally through the entrance of the tunnel on Wednesday after problems with the machine forced them to stop digging last week and consider alternate rescue plans.
The mountainous terrain in Uttarakhand has proved a challenge to the drilling machine, which broke down as rescuers attempted to dig horizontally toward the trapped workers. The machine's high-intensity vibrations also caused more debris to fall.
On Wednesday evening, ambulances and a team of 15 doctors were sent to the accident site, PTI reported.
Relatives who had gathered there told PTI they were finally feeling optimistic, after days of anxiety and concern over the rescue and well-being of the workers.
Devashish, whose brother-in-law is among those stuck, said he spoke to him on Monday.
"Sonu repeatedly told me not to worry now and that we would meet soon," he said.
Authorities began supplying the trapped workers with hot meals, made of rice and lentils, through a 6-inch pipe earlier this week after days of them surviving off of dry food sent through a narrower pipe.
Oxygen is being supplied to them through a separate pipe.
Officials on Tuesday released a video, after a camera was pushed through the pipe, showing the workers in their construction hats moving around the blocked tunnel while communicating with rescuers on the ground through walkie-talkies.
Uttarakhand is dotted with Hindu temples, and highway and building construction has been constant to accommodate the influx of pilgrims and tourists.
The tunnel is part of the Chardham all-weather road, a flagship federal project connecting various Hindu pilgrimage sites.
