A week since 41 workers have been trapped inside an under-construction tunnel at Silkyara in Uttarakhand's Uttarkashi district that collapsed following a landslide on November 12. While the rest of the country celebrated Diwali, for these workers, it was darkness over light as portions of the Silkyara-Dandalgaon tunnel on the Brahmkhal-Yamunotri highway collapsed at 5.30 am on Sunday, the previous week. The Silkyara Tunnel, about 30 km from the district headquarters of Uttarkashi and a seven-hour drive from the Uttarakhand capital Dehradun, is part of the ambitious Char Dham all-weather road project of the central government.

Although contact had been established the very next day, the fall of new debris over the old has not given much luck to rescue workers there. Contact was established with the trapped workers through a pipe meant to supply oxygen to them and they have been reported to be safe.?

Although the trapped workers are being supplied with food, water, oxygen, electricity, and medicines some of them complain of nausea and headache. However, the efforts have been suffering a setback when more rubble fell from the cavity created by the cave-in and caused minor injuries to two labourers.

On Monday, the government said that it has taken a five-point action plan where five options have been decided and five different agencies were detailed to carry out these operations. ?Five agencies namely Oil and Natural Gas Corporation (ONGC), Sutluj Jal Vidyut Nigam (SJVNL), Rail Vikas Nigam Limited(RVNL), National Highways and Infrastructure Development Corporation Limited (NHIDCL), and Tehri Hydro Development Corporation Limited (THDCL) have been assigned responsibilities.

While rescue operations are underway, officials associated with the same have allegedly contacted a rescue company in Thailand that had saved children trapped in a cave there in 2018. Officials are said to have also contacted Norway’s NGI agency to obtain specific suggestions for operations inside the tunnel.

As the rescue operations give a tough battle to authorities, here we look at other incidents that saw arduous rescue efforts in recent times.

1. Thai cave rescue?

In 2018, a junior association football team with 12 members aged between 11 and 16 along with their 25-year-old coach were rescued from Tham Luang Nang Non, a cave system in Chiang Rai province, northern Thailand after a week of remaining stranded. ?Shortly after they entered, heavy rainfall began and partially flooded the cave system, blocking their way out and trapping them deep within. With rising water levels posing a great level of danger, the rescue operation required nearly 10,000 people, including more than 100 divers, scores of rescue workers, representatives from about 100 governmental agencies, 900 police officers, and 2,000 soldiers.

2. Titan submersible rescue?

In June 2023, five men aboard the Titan submersible which lost contact with the after 1 hour and 45 minutes of the 13,000 ft journey below the sea, saw one of the most difficult rescue mission attempts. However, the submersible could not be located and no traces of the people onboard were found. After a five-day search, it was informed by the United States Navy's (USN) sonar detection of an acoustic signature consistent with an implosion around the time communications with the submersible ceased, suggesting the pressure hull had imploded while Titan was descending, resulting in the instantaneous deaths of all five occupants.

3. Rescuers move US caver

American explorer and speleologist, or cave expert, Mark Dickey was rescued after a difficult battle of one week from a cave in southern Turkey. The 40-year-old man got stuck in a section of the cave system known serendipitously as "Camp Hope” and was hit with gastric pain that turned into bleeding and vomiting while helping to chart the cave system — the country's third deepest and sixth longest — leaving him stuck more than 3,200 feet underground. Nearly 200 people from seven European countries and Turkey, including fellow cavers and medics, descended on the Morca cave system and had to dig up a path higher than New York's Empire State Building.