Search and rescue teams are combing through mud and debris across affected communities, while fresh warnings have raised fears of another possible deluge.

China said a "barrier lake" created by the first wave of floodwaters and debris was at risk of breaching.

In Nuwakot district, trucks were partially buried in mud and buildings surrounded by debris as police and rescue workers searched the area and helped people to safety.

Police said 28 bodies had been recovered in Nuwakot by Thursday evening.

Chitwan recorded the highest death toll, with 137 bodies recovered, while another 87 were found in Nawalparasi East. Rescue teams continue searching devastated river corridors for survivors and bodies.

The flood first tore through Rasuwa before surging downstream through the Trishuli and Narayani river systems. Settlements were destroyed, while roads, bridges and other infrastructure were damaged.

Nepal's Department of Hydrology and Meteorology said preliminary satellite imagery suggested an ice and rock avalanche may have blocked the Lhende River upstream.

The blockage may have created a temporary debris dam that later burst, sending water downstream. Some scientists have suggested a collapsed glacier may have caused the disaster.

Officials said the exact cause remained under investigation.