The storm -- the 10th to hit Vietnam this year -- made landfall late on Sunday, generating winds of 130 kilometres (80 miles) per hour.

Thousands of houses and businesses have been damaged or destroyed, authorities in three provinces told AFP.

Images published by AFP showed corrugated metal roofs blown off buildings and household debris strewn across saturated streets in coastal Nghe An province.

"The wind blew my roof to the sky and then it fell down, breaking everything. I had to cover my head and rushed to my neighbour's house to be safe," Trinh Thi Le, 71, in central Quang Tri province, was quoted as saying by state-run Tuoi Tre newspaper.

At least nine people were killed when a typhoon-related whirlwind swept through northern Ninh Binh province early on Monday, according to the local disaster agency.

One person was killed in the province of Hue and another in Thanh Hoa, while about 20 were missing, local and national disaster authorities reported.

Among those unaccounted for were nine people whose fishing boats were lost at sea Sunday night after their vessels were unmoored during strong winds and currents, police said.

More than 53,000 people were evacuated to schools and medical centres converted into temporary shelters ahead of Bualoi hitting Vietnam, the environment ministry said.

Four domestic airports and part of the national highway were closed on Monday. More than 180 flights have been cancelled or delayed, airport authorities said.

Parts of Nghe An and the steel-producing central province of Ha Tinh were without power, and schools were closed in affected regions.

Since making landfall in Vietnam, Bualoi has weakened as it moves towards neighbouring Laos.

The storm battered small islands in the centre of the Philippines last week, killing at least 11 people and forcing 400,000 to evacuate.

In Vietnam, 175 people were killed or went missing due to natural disasters from January to August this year, the General Statistics Office (GSO) said.

Total damages were worth about $371 million, almost triple the amount of the same period in 2024, the GSO said.

Scientists warn that storms are becoming more powerful as the world warms due to the effects of human-driven climate change.

Typhoon Yagi killed hundreds of people in Vietnam in September last year and caused economic losses worth $3.3 billion.