Eight Afghan labourers who were on their way to work at a US military base in Logar province have been shot dead, local officials say.

The men, aged between 15 and 25, were in a van when they were stopped by gunmen, forced out and shot, a local government spokesman said.

No group has said it carried out the attack, but local officials believe it could have been the Taliban.

The attack comes as the country observes the holy month of Ramadan.

The Taliban have said they plan to continue their attacks during this traditional Muslim period of fasting, the BBC's Sanjoy Majumder in Kabul reports.

The attack took place in the early hours of Thursday morning in the Pad Khwab area of Logar's capital, Pol-e-Alam.

The men were all from a nearby village and their bodies have been handed over to their families.

Logar lies just south of the Afghan capital, Kabul, but the Taliban are known to be active particularly in volatile areas of the province close to the border with Pakistan.

This is thought to be one of the first such incidents in the capital, but militants around the country have targeted civilians who work for security forces in the past.