Rasuwa, Sept. 1 -- A rescue operation is underway at the Chilime hydropower tunnel near Syabrubesi village in Nepal's Rasuwa district, after devastating flash floods swept through the region, trapping an unknown number of workers inside.

Nepal Police Deputy Inspector General D Regmi said the tunnel houses several buildings and, being a hydropower facility, has many workers during operational hours.

"There are many buildings inside this tunnel, and since it is a hydro tunnel, many people also work there...The tunnel is also damaged, and floodwaters have entered the tunnel," Regmi said, adding that rescue teams began operations at around 7 AM on Tuesday to determine exactly how many people remain trapped inside.

"We had reached there bef...