At least seven workers have been killed and 13 others injured after a tunnel accident at a construction site in India’s northern state of Uttarakhand, local officials said.

The incident occurred late Thursday at a tunnel being constructed as part of a state-run hydropower project. A landslide caused water and debris to surge into the tunnel, trapping workers inside.

Uttarakhand Chief Minister Pushkar Singh Dhami said a large-scale rescue operation was underway to reach workers who remained trapped, describing the effort as a “war-like rescue operation.”

India’s State Disaster Management Authority said three workers were still missing, while authorities continued efforts to locate and evacuate them.

“Evacuating every worker safely is our top priority,” Dhami said in a social media statement.

Rescue teams faced difficult conditions inside the flooded tunnel, with rising water levels and continuing seepage from the surrounding rock.

Videos released by local authorities showed rescue personnel wearing head-mounted lights and using makeshift rafts to reach the flooded sections.

Amrit Lal Meena, commander of a National Disaster Response Force team, said rescuers encountered significant amounts of water when they arrived and that the water level subsequently increased considerably.

Emergency teams continued working to drain the tunnel, clear debris and reach the missing workers.

Uttarakhand has experienced heavy monsoon rainfall in recent days, increasing the risk of landslides and flooding across the mountainous region.

The latest accident has also renewed concerns over the safety and environmental consequences of large infrastructure and hydropower projects in the fragile Himalayan region.

India has experienced a series of deadly incidents at major construction sites in recent years. In July, 20 workers were killed after becoming trapped in a tunnel linked to another state-run hydroelectric project in the northeastern state of Sikkim.

In Uttarakhand in 2023, 41 workers were rescued after spending 17 days trapped inside a collapsed tunnel.

The latest tunnel accident comes amid a wider wave of flooding and landslides across India during the annual monsoon season, which began in June.

Hundreds of people have reportedly died in weather-related disasters across the country since the start of the season.

Environmental experts have warned that climate change, combined with poorly planned or excessive development in environmentally sensitive Himalayan areas, may be increasing the frequency and severity of floods, landslides and other disasters.

Authorities in Uttarakhand are continuing the rescue operation as efforts remain focused on locating the three missing workers and ensuring the safe evacuation of those still inside the tunnel. (ILKHA)