Hanoi  - Vietnam's death toll from typhoon Ketsana has risen to 74, with 12 more reported missing, national storm and flood authorities said Thursday.

Another 179 people were reported injured, including some in critical condition.

The typhoon brought winds of 117 kilometres per hour (kph) when it came ashore in the central province of Quang Nam, and dumped up to 900 millimetres of rain. More than 6,000 houses were destroyed by floods, wind or landslides, along with dozens of schools and health care centres.

There were reports of 116 fishing boats sunk. More than 17,000 hectares of rice were submerged, and 107,000 poultry were reported killed.

Preliminary estimates by the Storm and Flood Control Committee showed losses of 136 million dollars, including 88 million dollars in Quang Nam.

Vietnam's sole oil refinery at Dung Quat, damaged by power outages, had still not resumed operations as of Thursday. The multibillion-dollar refinery, which began operations this summer, had been struggling to reopen after a cracked valve led to a shutdown in late August.

In the city of Danang, the typhoon caused a pipeline to rupture at a petrol storage depot, attracting hundreds of people who scooped up the loose fuel, the Vietnam News reported.

Streets in many towns, including the historic tourist centre of Hoi An, remain flooded.

Vietnam's national weather centre said Thursday that river levels were gradually declining, but warned of continued potential for flooding and landslides.

Two reservoirs in mountainous Kon Tum province are at risk of breaching, threatening thousands of people living downstream.

Vietnam Airlines resumed operations Wednesday to central provinces after canceling its flights Monday and Tuesday due to the typhoon. On Thursday, it added several flights to ease the backlog of passengers stuck in the region.

The typhoon was downgraded to a tropical low pressure zone as it headed inland, but still caused heavy flooding in Laos and a reported 10 deaths in Cambodia.

Ketsana killed at least 277 people when it struck the Philippines over the weekend, causing estimated damage of 100 million dollars. (dpa)