Two people were killed and thousands of homes damaged as Vietnam's coast was lashed by Typhoon Son-Tinh, authorities said Monday, after the storm caused deadly landslides and floods in the Philippines.

Strong winds destroyed large tracts of crops, brought down power lines and ripped the roofs off houses after Son-Tinh, which has been downgraded to a tropical depression, made landfall in the north of the country late Sunday.

Two people were confirmed killed while two others were missing, an official from the National Committee on Flood and Storm Control in Hanoi told AFP, adding that it was the biggest typhoon to hit Vietnam since the start of the storm season, with wind speeds of up to 140 kilometres (87 miles) per hour.

The wind also felled a 180-metre television tower, the tallest in northern Vietnam, in Nam Dinh City, according to state-run Tuoi Tre newspaper.

Vietnam is hit by an average of eight to 10 tropical storms every year, often causing heavy material and human losses.

More than 50,000 people were evacuated in preparation for the bad weather, while authorities imposed a sea ban in some areas and dozens of domestic flights were cancelled.

Son-Tinh left 27 people dead and nine missing in the Philippines, according to figures from the government's civil defence office on Monday, after it tore down trees and caused flash floods and landslides.

In China's southern province of Hainan, one person was killed, five are missing and about 126,000 were evacuated from their homes because of the storm, the official Xinhua news agency said.

The agency, quoting information from the civil affairs ministry, said more than 700 houses were destroyed and over 2,400 damaged.

It said 41,100 hectares (101,560 acres) of crops were affected, leading to direct economic losses of 910 million yuan ($145.7 million).