Hanoi  - Vietnam's death toll from Typhoon Ketsana has risen to 159, with 17 people still missing, national storm and flood authorities said Monday.

The count of houses destroyed or swept away in floods had risen to over 21,000, said Tran Anh Trung of the Steering Committee for Flood and Storm Control in central Vietnam. Over 250,000 were heavily damaged.

Total damage is now estimated at some 700 million dollars. Some 44,000 hectares of rice paddies were flooded by the storm.

Vietnamese Prime Minister Nguyen Tan Dung said last week some 600,000 people had been evacuated to safety.

The typhoon brought winds of 117 kilometres per hour (kph) when it came ashore Tuesday in the central province of Quang Nam, dumping up to 900 millimetres of rain.

Streets in many towns, including the historic tourist centre of Hoi An, remain flooded. Many people have had to move out of their ancient houses because the structures are in danger of collapsing at any time.

Vietnam's sole oil refinery at Dung Quat, damaged by power outages during the storm, resumed operations over the weekend.

Weather authorities reported Monday that tropical storm Parma has crossed the northern Philippines and expected to head slowly south-west, a trajectory that could take it towards Vietnam. It currently has wind speeds of some 100 kph.

The 159 deaths caused by Ketsana brought Vietnam's death toll from natural disasters to at least 300 so far this year.

In 2008, natural disasters killed 550 people in Vietnam and caused damage amounting to more than 700 million dollars. (dpa)