KABUL, (AFP) – Insurgents beheaded six Afghan policemen after overrunning their checkpost, NATO said Wednesday, as authorities claimed to have foiled suicide attacks on a landmark international conference in Kabul.

The beheading took place Tuesday in the northern province of Baghlan, a region where insurgents have gained strong footholds in recent years, NATO’s International Security Assistance Force (ISAF) said.

The military said police “successfully repelled” an insurgent attack on a school, clinic and the district governor’s building in Dahanah-ye Ghori, killing several insurgents.

But added: “During the attack, insurgents overran a police checkpoint and killed the police officers by cutting off their heads.”

ISAF condemned the “brutal” killings.

Abdul Majeed, provincial governor confirmed that six Afghan policemen had been killed in their post but refused to give details.

In southern Afghanistan, heartland of the Taliban insurgency, a bomb attack killed another NATO soldier on Wednesday, bringing to at least 384 the number of foreign soldiers to have died in the war so far this year.

In Kabul, Afghanistan’s intelligence agency claimed to have foiled a string of attacks planned by the Taliban in a bid to disrupt a major international conference attended by representatives from over 70 nations and organisations.

A spokesman for the National Directorate of Security told reporters that militants planned to carry out suicide bombings, and launch mortars and rockets to interrupt Tuesday’s gathering in the Afghan capital.

UN Secretary General Ban Ki-moon and US Secretary of State Hillary Clinton were among those who attended the one-day talks.

Days before the conference, intelligence agents stormed a house in the capital and detained five militants, spokesman Sayed Ansary said.

A female “suicide bomber” blew herself up as the agents broke into the compound, he claimed.

Ansary said the five men “confessed” to planning a suicide bombing and to intended to launch up to 20 mortars on the gathering at the foreign ministry.

Another five-men group was captured in eastern suburbs and a man carrying five missiles on the western approach to the capital, Ansary said.

He alleged that all those detained were planning attacks.

ISAF has also previously claimed that several insurgents were shot dead or arrested in raids to thwart attacks on the conference.

The meeting endorsed a plan by President Hamid Karzai for Afghanistan to take responsibility for national security by the end of 2014, allowing tens of thousands of US and NATO forces to leave.

On the same day, an Afghan soldier shot dead two US civilian trainers during a training exercise in the northern province of Balkh.

The shooter and another Afghan soldier also died at the camp outside the provincial capital Mazar-i-Sharif.

The Afghan defence ministry said that the deaths were caused by an argument.

“It’s said that after a verbal argument between an army soldier and his two US trainers the soldier opened fire, killing the two trainers and injuring another one,” the Afghan defence ministry said.