KANDAHAR: A NATO soldier and four civilians were killed in separate home-made bomb attacks in southern Afghanistan on Sunday, officials and the military alliance said.

The International Security Assistance Force (ISAF) said only that one of its troops was killed by an improvised explosive device in the volatile region, which has seen the fiercest fighting in the eight-year war with the Taliban.

Earlier, officials in Helmand province said a home-made bomb tore through a bus carrying a mine clearance team as they travelled along a dirt road near Daman district, killing four and injuring more than a dozen others.

"The deminers were travelling in a minibus. There was a remote-controlled bomb on the road. They struck the bomb," Daman district governor Sarajuddin Khan said.

He could not give a toll for the casualties but local public health official Mohammad Ibrahim said four people were killed and 14 others were wounded.

Taliban militants, ousted from power in a US-led invasion in late 2001, have been waging an increasingly deadly insurgency against the Western-backed government in Kabul, particularly using roadside bombs.

The US military has said the increasingly sophisticated devices killed 322 coalition soldiers and wounded 1,813 in 2009 -- double the number in the previous 12 months.

Eighty-one US and NATO troops were killed by IEDs between January and March this year, according to Pentagon figures.

The latest death takes to 154 the total number of foreign soldiers killed in Afghanistan this year, according to a French news agdne count based on the independent icasualties.org website, which tracks coalition deaths in Iraq and Afghanistan.

The United Nations has said that most civilian deaths -- 2,412 last year -- were caused by Taliban bombs and suicide attacks.

Three people were killed and five wounded on Friday when their van hit an IED intended for US and Afghan forces in western Herat province, police said.