•On Wednesday evening, officials said they were confident the workers could be rescued by Thursday afternoon.
•Authorities established contact with the trapped men hours later and were supplying them with provisions.
Rescue workers drilling to free 41 workers trapped in a tunnel in India's Uttarakhand state are close to breaking through to them, officials say.
On Wednesday evening, officials said they were confident the workers could be rescued by Thursday afternoon.
The workers were building the tunnel when a part of it caved in on 12 November due to a landslide.
Authorities established contact with the trapped men hours later and were supplying them with provisions.
These included oxygen, dry food and water through a pipeline that was laid for supplying water to the tunnel for construction work.
Officials have been giving regular updates and have indicated they are making good progress.
But family and friends of the workers have been increasingly anxious - and angry, wondering why it is taking so long to get the men out.
On Monday, anxious relatives who had crowded around the tunnel experienced some relief when an endoscopic camera - slipped inside through a new pipe - captured footage of the workers. Officials asked them to identify themselves in front of the camera and assured them that they would be rescued soon.
The new pipe is wider and authorities say they can now supply more oxygen, food and other essentials such as medicines, mobile phones and chargers.
It was also used on Tuesday to give the workers their first hot meal in 10 days, with rescuers packing khichdi (a rice and lentil dish) in bottles and sending them inside.
Rescuers resumed drilling near the mouth of the tunnel at 02:00 local time (20:30 GMT) on Wednesday, officials told the BBC.
By Wednesday evening, just 12m (39ft) of debris separated the workers from freedom, and officials told the BBC the would be out by 08:00 Thursday local time (02:30 GMT).
That was before the drill hit iron rods, delaying efforts as it was withdrawn and metal cutters deployed. However, officials remained confident the workers would be out by Thursday afternoon.
Until now, they have managed to insert four pipes, each 900mm wide, through the debris - officials say they are now pushing through 800mm wide pipes into them and further on through the debris wall using a telescopic tunnelling method.
The plan is to send multiple pipes of differing widths through the estimated 60m (197ft) debris wall to create a micro-tunnel through which the workers can crawl out through.
But the operation has encountered several delays and obstacles due to loose soil, hard rock and falling debris, slowing the rescue.
Other plans are also progressing - attempts are under way to reach the men through the other end of the tunnel.
A top official said on Wednesday that they had also constructed a track and transported equipment to begin vertical drilling, through the top of the mountain.
At the press briefing on Wednesday, an official said they hoped to share some "good news" soon. He also added that doctors are at the scene and speaking to the trapped workers.
The Silkyara tunnel in Uttarkashi district is part of the federal government's ambitious highway project to improve connectivity to famous pilgrimage spots in Uttarakhand. The mountainous state, where several Himalayan peaks and glaciers are located, is home to some of the holiest sites for Hindus.
The surrounding area is a mountainous region and quite rugged. There are large rocks and boulders to contend with even just walking the perimeter.
The region is ecologically fragile and vulnerable to earthquakes and landslides.