At least 95 people were killed in Nepal on Wednesday after a massive flood tore through the border region with Tibet, a police spokesman told AFP.
"So far 95 deaths have been reported," spokesman Abi Narayan Kafle said, adding that some 28 police personnel were also missing.
A torrent of mud and debris burst from the banks of a river between China and Nepal, burying buildings and triggering a frantic search for survivors.
Chinese state media reported "major casualties" from a mudslide at a Tibet trade hub on China's side of its border with Nepal, and President Xi Jinping ordered an "all-out" rescue effort.
"I got a call from (my brother-in-law) this morning, and they were crying and said their entire house had been swept away. Three family members were rescued, but his brother is still missing," said 56-year-old Raju Bhadel.
Police in Nepal reported the death toll hit at least 19, but 384 tourists -- 291 of them foreigners -- were unaccounted for over eight hours after the disaster struck.
Nepal's tourism board, which released the figure, said Americans, Indians, an Australian, Malaysians and Britons were among those unaccounted for.
Images shared by Nepali police showed floodwater surging through a river, sweeping away houses in its path, while AFP images depicted the top floor of a house sticking out from muddy soil.
A police spokesman told AFP earlier that authorities did not know the extent of the damage but said they had "alerted people who are staying near the riverside to relocate".
The Nepal Army said it had deployed helicopters and disaster response personnel to the affected area.
The Nepal Electricity Authority said about 430 megawatts of production capacity, including from hydropower and solar facilities, has been damaged.
"The disaster has damaged the production, transmission and distribution facilities of the Authority... resulting in disruption of electricity supply," it said.
Sarthak Shrestha, a remote sensing and geo information analyst at the Kathmandu-based International Centre for Integrated Mountain Development (ICIMOD), said a preliminary assessment showed "no anomalies" from China's side of the border.
"We believe a rock-ice avalanche occurred in Nepal, blocking the Lhende river and causing the cascading flood event," he told AFP.