KABUL: Five US soldiers were killed Saturday in separate incidents while battling the Taliban-led insurgency in Afghanistan, as NATO said its troops had accidentally killed six Afghan civilians.

Three of the soldiers died in eastern Afghanistan and two were killed in the south, NATO`s International Security Assistance Force (ISAF) said.

A sixth US serviceman also died Saturday, in an accidental explosion, an ISAF official told AFP on condition of anonymity.

The six deaths bring to 352 the toll of international soldiers in the Afghan war this year, according to a tally kept by AFP based on the icasualties.org website.

It was the highest one-day toll since the deaths of ten foreign soldiers on June 21, which equalled the worst day of the year for international forces.

An ISAF statement said the causes of death in the east were small-arms fire, a home-made bomb attack and an unspecified "insurgent attack".

The two soldiers who died in the south were involved in separate attacks with homemade bombs, known as improvised explosive devices (IEDs).

US soldiers are known to be involved in a major operation in Kunar province, on Afghanistan`s eastern border with Pakistan, though ISAF would not confirm that the deaths in the east were related to the offensive.

While it is ISAF policy not to reveal the nationalities of the soldiers, an official who asked not to be identified said all were Americans.

ISAF earlier said its troops had killed six civilians accidentally, a day after reporting that six Afghan soldiers had died in a "friendly fire" incident.

Civilian casualties are an incendiary topic with Afghans, who increasingly regard the presence of international troops in their country as the main cause of violence that has wracked Afghanistan for almost nine years.

ISAF said "artillery fire from an ISAF unit killed six civilians and wounded several others in Jani Khel on Thursday", referring to a district of Paktia province, south of Kabul.

The dead had been removed before ISAF units had arrived on the scene, the force said, and so it was not immediately clear that people had been killed by what it said were "errant rounds".

That statement came after ISAF said a helicopter patrol in southern Ghazni province had opened fire on a group of Afghan soldiers on Tuesday, mistaking them for militants planting bombs by a roadside.

While reports of friendly fire incidents are not common in Afghanistan, they add to a perception that foreign forces do not take enough care to avoid killing Afghans, military or civilian.

Command of the 140,000 troops in Afghanistan has just been taken over by US General David Petraeus who is under some pressure to change the rules of engagement, as some soldiers believe they restrict defensive action.

Petraeus has not publicly ruled out making changes, though observers in Kabul said he is unlikely to alter rules he was instrumental in formulating and which are credited with cutting civilian casualties.

The United Nations said in a recent report that most civilian casualties in Afghanistan are caused by the Taliban, using IEDs or in suicide attacks.

The United States, with almost 100,000 of the 140,000 international troops in Afghanistan, is bearing the greatest burden of a rising death toll, with 224 soldiers dead this year so far, and 1,171 since the war began in 2001.

June saw more than 102 foreign troops deaths, a monthly record since the war began with the 2001 US-led invasion to overthrow the Taliban regime.

IEDs are the biggest killer, with a June UN report marking a 94 percent leap in IED incidents in the first four months of this year compared to 2009.

The country`s intelligence service said Saturday it had captured a six-man "terrorist cell" in Kabul, thwarting attacks on the capital involving almost half a tonne of explosives.

National Directorate of Security (NDS) spokesman Sayeed Ansari told reporters the gang, linked to the brutal Pakistan-based Haqqani network, had prepared attacks on the capital, and had been involved in attacks elsewhere.

Separately, a remote-controlled bomb rigged up to a motorbike detonated in the centre of southern Kandahar city on Saturday, killing at least one person, the deputy police chief for Kandahar province, Fazel Ahmad Khan Shairzad said.

BDST: 2126 HRS, July 10, 2010