Torrential rains have caused havoc, landslides and a bridge collapse, and swept a bus into a torrent.
At least 59 people have been killed in Vietnam amid landslides and floods triggered by Typhoon Yagi, according to state media reports.
The typhoon was Asia’s most powerful storm this year and made landfall on Vietnam’s northeastern coast on Saturday, after causing havoc in China and the Philippines.
Among the victims were six people, including a newborn baby and a one-year-old boy, who were killed in a landslide in the Hoang Lien Son mountains of northwestern Vietnam.
Their bodies were discovered on Sunday, a local official told the AFP news agency.
Other victims included a family of four who were killed after heavy rain caused a hillside to collapse onto a house in mountainous Hoa Binh province in northern Vietnam, state media reported.
On Monday morning, a passenger bus carrying 20 people was swept into a flooded stream by a landslide in mountainous Cao Bang province.
Rescuers were deployed, but landslides blocked the path to where the incident took place.
In Phu Tho province, rescue operations were continuing after a steel bridge over the engorged Red River collapsed.
Reports said 10 cars and trucks, along with two motorbikes, fell into the river.
Three people were pulled out of the river and taken to hospital, but 13 others were missing.
The Vietnamese government said the storm disrupted power supplies and telecommunications in several parts of the country, mostly in Quang Ninh and Hai Phong in the northeast.
The weather agency on Monday warned of more floods and landslides, noting that rainfall had ranged between 208mm and 433mm (8.2 inches to 17 inches) in several parts of the region over the past 24 hours.
“Floods and landslides are damaging the environment and threatening people’s lives,” the National Centre for Hydro-Meteorological Forecasting said in a report.
Yagi weakened to a tropical depression on Sunday, but several areas of the port city of Hai Phong were under half a metre (1.6 feet) of water and there was no electricity.
At Ha Long Bay, a UNESCO World Heritage Site about 70km (43 miles) up the coast from the city, the disaster management authority said 30 vessels sank after being pounded by strong wind and waves.
The typhoon also damaged nearly 3,300 houses, and more than 120,000 hectares (296,500 acres) of crops in the north of the country, the authority said.
Before arriving in Vietnam, Yagi tore through southern China and the Philippines, killing at least 24 people and injuring dozens of others.
Typhoons in the region are now forming closer to the coast, intensifying more rapidly, and staying over land for longer due to climate change, according to a study published in July.