The unprecedented flash flood in Nepal and Tibet has killed more than 900 people and left nearly 4,800 missing, authorities said Monday, as rescue efforts entered a sixth day.

"We are working in search and rescue of the stranded people from hills, settlements and river areas," Brigadier General Raja Ram Basnet, Nepal's army spokesman, said.

Nepalese authorities said many bodies have been recovered in southern Nepal, miles away from areas hardest hit by last Wednesday's floods.

Local media reported that some victims were being buried in mass graves, sparking controversy in the predominantly Hindu country, where cremation is the customary funeral rite.

What are the numbers saying?

According to the latest numbers, reported by authorities in Nepal and China:

• Deaths in Nepal: 903
• Total missing in Nepal: 4,247
• Citizens: 3,655
  • Hydropower projects workers: 933
  • Nepali army soldiers: 45  
  • Police personnel: 38  
  • Customs and immigration officers: 19
• Foreigners: 592
• Deaths in Tibet: 16
• Total missing in Tibet: 546

Multiple foreign rescue teams are assisting local authorities in reaching workers trapped in hydropower tunnels in Nepal. Officials said at least 90 people remain trapped in multiple tunnels.

In India's Uttar Pradesh state, authorities recovered 17 bodies from rivers flowing from Nepal.

The bodies are believed to be linked to the floods but have not been included in the official death toll pending identification.

What caused the floods?

Several scientists believe a glacier collapse in the Himalayas may have triggered last week's disaster, sending huge volumes of water down a river valley.

The flood, carrying rock, ice, mud and debris surging through the Himalayan mountain river systems below, swept through areas near the Chinese border, ravaging entire towns and damaging hydropower plants.

Edited by: Rana Taha

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