Rainfall from Wednesday to Thursday caused landslides in Dien Bien, Lai Chau and Son La, while the national weather agency warned of continued risks of flash floods and landslides as more rain is forecast.
Over the past 24 hours, rainfall reached 181 mm in parts of Lao Cai, 145 mm in Lai Chau and 140 mm in Tuyen Quang, according to the National Centre for Hydro-Meteorological Forecasting.
The agency said saturated soil had significantly increased the risk of flash floods along small rivers and streams, as well as landslides on steep slopes. It forecast a further 20-50 mm of rain over the next three to six hours, with isolated areas expected to receive more than 90 mm.
In Dien Bien, landslides blocked sections of National Highway 6 and National Highway 12, while thunderstorms and more heavy rain are forecast through Friday.
In Son La, a landslide struck a car on National Highway 279D on Thursday morning. No casualties were reported.
