India hydropower tunnel collapse: Death toll rises to 25 as rescue effort ends

In this image provided by the Information and Public Relations Department, Government of Sikkim, rescue workers stand outside an under-construction tunnel at a hydropower project in Samardung village, about 40 kilometers (25 miles) from Gangtok, India, Wednesday, July 22, 2026. (Government of Sikkim via AP)

GUWAHATI, India — Authorities recovered the bodies of the remaining 13 workers trapped inside a collapsed hydropower tunnel in India, taking the death toll to 25 as authorities ended the rescue operations on Thursday.

Multiple agencies had made sustained and coordinated rescue efforts in the four days since a gas explosion ripped through the tunnel. Following the recovery of all the missing employees, teams carried out a final inspection of the tunnel, the state government of Sikkim said in a statement.

The blast occurred Monday at the 500-megawatt Teesta Hydroelectric Project about 40 kilometres (25 miles) south of the state capital Gangtok in the Himalayan state.

A buildup of methane gas triggered the explosion, trapping dozens of workers underground. Rescue efforts were hampered by the toxic gas inside, officials said.

The government said it formed a high-level committee to investigate the disaster and recommend safeguards against to prevent such accidents in the future.

Construction accidents are not uncommon in India, where rapid infrastructure growth often collides with fragile geology, construction lapses, extreme weather and safety standards.

The Teesta River basin, where the hydropower project is being built, lies in a seismically active region marked by young, fragile rock formations riddled with fractures and underground pockets that can trap ancient gases. Seismic activity and unpredictable underground conditions make tunnel projects especially risky in the region, according to experts.

A February explosion in a coal mine in neighboring Meghalaya state killed 18 workers. A tunnel section collapsed in 2023 in northern Uttarakhand state, trapping 41 workers for 17 days before they were rescued.

Wasbir Hussain, The Associated Press