As of 3 p.m. on September 30, rainfall across Son La ranged from 40 to 100 millimetres, with some stations recording more than 300mm, including 388.2mm at Muong Do 1 and 363.8mm at Bac Phong, according to the provincial Civil Defence Command.

The disaster left one person dead in Muong Bang commune and another missing in To Mua. Flooding affected 109 households, while four homes collapsed and 15 lost roofs. More than 40 families in To Mua, Long Sap and Van Ho were forced to evacuate. About 100 hectares of rice fields, 220 hectares of corn, and nearly 15 hectares of vegetables and fruit crops were inundated.

Transport and infrastructure also suffered, with 41 roadblocks reported - 17 of which remain impassable due to flooding and landslides. Fifty-three transformers were damaged, disrupting power supply to 3,203 customers, while 15 schools were flooded or hit by landslides.

The provincial People’s Committee has dispatched inspection teams and mobilised military, police and militia forces to evacuate residents and repair roads. Power sector crews are working to restore service, while local authorities are assessing damage and assisting households in stabilising their lives.

With rain forecast to continue, the provincial Civil Defence Command has urged heightened vigilance and readiness in response efforts.