India, Aug. 31 -- As many as 537 workers and employees remained unaccounted for at nine hydropower projects in Nepal's flood-hit Rasuwa and Nuwakot districts, with rescue teams intensifying efforts to reach people believed trapped inside tunnels blocked by mud and debris.

Rescue operations have been hampered by mud and debris blocking tunnel entrances, damaged infrastructure, difficult terrain and adverse weather, prompting Nepal to seek specialised assistance from India, China and other countries. According to the Independent Power Producers' Association in Nepal (IPPAN), 898 workers and employees at nine hydropower projects in the two districts were initially reported out of contact following the August 26 floods.

Of them, 361 have be...