At least 15 people in Vietnam are now known to have died as a result of Typhoon Xangsane, which buffeted central provinces over the weekend.
The typhoon has destroyed thousands of homes
The coastal city of Danang was hardest hit, with hundreds of people injured and thousands of homes destroyed.
The typhoon devastated areas of the Philippines last week, killing at least 76 people and leaving millions without power and clean drinking water.
Xangsane has now been downgraded to a tropical storm.
Four provinces in central Vietnam - Danang, Thua Thien-Hue, Quang Nam and Quang Ngai - bore the brunt of the typhoon.
"The areas in the typhoon's direct path looked like they were just bombarded by B-52s" Nguyen Ngoc Quang, deputy provincial governor of Quang Nam, told reporters.
Trees were uprooted and roofs blown off houses, while there was concern for fishermen who did not return to port.
Electricity and telephone lines were also cut in many areas, with air and train travel disrupted. The worst of the damage was reported in Danang, where the typhoon hit at around 0900 local time (0200 GMT) on Saturday.
The cost of damages in Danang alone will amount to $200m, the authorities estimate, with more than 5,000 houses were washed away, 166,000 damaged and 19 vessels sunk.
"When I returned home, there was nothing left," said Danang resident Pham Thi Thanh.
Flooding was also reported in the port town of Hoi An, a popular tourist spot, and the Huong River was said to be rising in the former imperial capital of Hue.
Ahead of the storm, authorities had reinforced sea defences and evacuated abut 200,000 residents from vulnerable central areas.
While the typhoon has now been downgraded to a tropical storm, there are still strong risks of landslides and further flooding in the hills.
Xangsane caused severe damage in the Philippines, leaving many roads and bridges impassable. Dozens of people are still missing there.
The typhoon was the strongest to hit the capital, Manila, in 11 years, weather officials said.