Kabul - Four US-led coalition soldiers and an Afghan national were killed in a roadside bomb blast in eastern Afghanistan Wednesday as US Defence Secretary Robert Gates visited the war-torn country.

The foreign soldiers' deaths were confirmed in statement issued by US military authorities in Bagram, the main US base in the country, but did not disclose the nationality of the deceased soldiers, nor did it say where exactly in the eastern region the incident took place.

Most of the troops serving under the coalition banner are from the United States.

Taliban militants, meanwhile, said in a statement posted on their website that they attacked a US battle tank in Khoshamand district of the south-eastern province of Paktika with a roadside mine on Wednesday, killing five US soldiers and destroying their vehicle.

It was not immediately clear if the Taliban and the US forces were referring to the same incident.

The soldiers were killed the same day as US Defence Secretary Robert Gates was visiting Afghanistan.

Gates arrived in Kabul late Tuesday evening and held talks with Afghan President Hamid Karzai in his presidential palace Wednesday morning and coalition commanders to discuss the ongoing war against the resurgent Taliban.

With over three months left in 2008, the year has already been the bloodiest period for the US forces since the ouster of the Taliban regime in 2001. The US military death toll has surpassed last year's record of 111.

More than 33,000 US troops are in the country serving with the NATO-led forces and under a separate coalition forces banner led by American generals. The US government recently announced that it will send an additional 4,500 soldiers to the country by January.

However, NATO's top general in Afghanistan, David McKiernan, has said that he needed 10,000 extra international troops to fight the insurgents, who have grown in numbers recently.

Taliban militants, who lost power after a US-led invasion in the wake of the September 11, 2001 attacks, rely heavily on the use of suicide and roadside bomb attacks in their campaign to bring down the Western-backed Afghan government.

In a separate incident, the coalition said it killed two militants and detained two others in Andar district of the southern province of Ghazni on Tuesday.

The combined forces found multiple AK-47s, three rocket-propelled grenades, a rocket launcher, multiple hand grenades, homemade bomb-making material and military style clothing during a search of the targeted compound, the statement said.

Also on Tuesday, in Muqur, another district in Ghazni province, Afghan army forces killed two militants and arrested 25 other suspected militants, the defence ministry said.

An Afghan soldier was killed and another wounded in a Taliban attack in Wardak, a province close to Kabul city on Tuesday, the statement said.

More than 4,000 people - mostly insurgents but including more than 200 international soldiers - have been killed in Afghan clashes so far this year. dpa