Kathmandu - Monsoon floods and landslides have killed at least 66 people across Nepal and India but officials fear that figure could almost double as rescuers search for dozens believed lost under mud and in submerged villages. Authorities Sunday upgraded the death toll from flash flooding across landlocked Nepal to 49 as the water kept rising, forcing thousands to flee for higher ground. "Another 17 are missing. Search and rescue works are underway but the water levels have not declined yet," said Shankar Hari Acharya, the chief of Nepal's national emergency centre. The Red Cross estimated a higher death toll of 53, with dozens more missing and injured and thousands of homes destroyed. In neighbouring India, rescuers were desperately trying to reach two packed buses swept into a gorge by a landslide so powerful it destroyed an entire stretch of highway. The coaches had stopped for a tea break around midnight Saturday in Himachal Pradesh when tonnes of rock and mud cascaded down a mountainside. Seventeen bodies have been recovered from the accident site in the Himalayan state, said Sandeep Kadam, a senior official at the scene. But dozens were still missing somewhere at the bottom of the ravine, with soldiers and rescuers clawing through the mud and rock to reach them.