Theflash floods are believed to have been triggered by a collapse or avalanche of ice and rock near the Nepal-Tibet border

The death toll in Nepal and Tibet from last week's catastrophic floods has hit 797 with more than 3,000 missing, authorities said.

Nepal has warned of another flash flood after water levels rose at an avalanche-formed lake near the Tibet border. The alert has deepened fears of a second disaster as rescuers search for the missing and the death toll climbs.

Nepal: The Nepal flood death toll has climbed to 469, making the disaster increasingly catastrophic as rescue teams continue operations in several