Landslides triggered by heavy rains blocked roads and damaged bridges in many localities, disrupting traffic and isolating a number of villages.
Seven towns and districts in Quang Binh have been at the high risk of landslides, and 1,903 local residents need to be evacuated.
Torrential rains have also caused power outages and flooding in Thua Thien-Hue province.
The steering office has asked the affected cities and provinces to seriously implement instructions of the Prime Minister and the office, timely inform local authorities and people about developments of natural disasters, and monitor residential areas vulnerable to flooding and landslides.
Localities need to take measures to protect dykes, reservoirs and production activities, and maintain search and rescue operations, the office said.
