Hanoi  - A bomb disposal unit has destroyed an unexploded 225-kilogram US Air Force bomb discovered by construction workers on a beach in a Vietnamese resort town, a local official confirmed Tuesday.

A military official in the seaside town of Dong Hoi, who asked to remain anonymous, confirmed a report in the Viet Nam News that workers had found the bomb buried 4 metres underground while building a seawall in an area near several hotels and restaurants.

The bomb, one of thousands dropped on Dong Hoi by US forces during the Vietnam War, was removed and destroyed by a bomb disposal unit on Monday.

Vietnamese unexploded ordnance (UXO) teams had an unusually busy month in August.

Dong Ngoc Nghia, commander of the Vietnamese Army's forces in Thua Thien-Hue province, said bomb disposal units had found hundreds of unexploded bombs in his province in August, including 17 bombs weighing 45 kilograms or more.

That compares with 40 such bombs found in all of 2008.

"We will destroy them next week," Nghia said. "The longer we leave them, the more dangers we face."

The bombs and shells were discovered in the A Luoi district in the mountainous western part of the province. The A Luoi valley, which includes the mountain known in the US as Hamburger Hill, was the site of fierce combat throughout the Vietnam War.

In November 2008, the head of Vietnam's bomb disposal centre told a conference in Ho Chi Minh City that an estimated 800,000 tons of bombs, landmines and artillery shells are still buried across the country, over an area of 6.6 million hectares.

Between 15,000 and 20,000 hectares are cleared of unexploded ordnance each year. At the current rate it will take Vietnam another 440 years to finish clearing the country.

According to the United Nations, 104,000 Vietnamese have been killed or injured by bombs, landmines and artillery shells since the end of the war in 1975. (dpa)