NEW DELHI (AP) — Twenty-three Indian army soldiers were missing Wednesday after a cloudburst triggered flash floods in the northeastern state of Sikkim, the army said in a statement.

The flooding occurred along the Teesta River in Lachen valley, the statement said, adding that some army camps and vehicles were submerged under watery mud and that search efforts were underway. The army said water released from a nearby dam also caused water levels to rise.

Defense authorities told the Press Trust of India news agency that 80 local residents have been safely evacuated so far. The agency reported that a bridge over the Teesta River was also washed away in the floods early on Wednesday.

Cloudbursts — sudden, very heavy rain — are defined as when more than 10 centimeters (3.9 inches) of rainfall occurs within 10 square kilometers (3.8 square miles) within an hour. They have the potential to cause intense flooding and landslides affecting thousands of people.

The mountainous Himalayan region where Sikkim is located has seen heavy monsoon rains this season. Nearly 50 people died in flash floods and landslides in August in nearby Himachal Pradesh state, while record rains in July killed more than 100 people over two weeks in northern India, as roads were waterlogged and homes collapsed.

Disasters caused by landslides and floods are common in India’s Himalayan region during the June-September monsoon season. Scientists say they are becoming more frequent as global warming contributes to the melting of glaciers there.

In February 2021, flash floods killed nearly 200 people and washed away houses in Uttarakhand.