The international coalition fighting in Afghanistan says a man dressed in an Afghan army uniform has killed a NATO service member in the southern part of the country.

The International Security Assistance Force said in a statement that it is investigating Saturday's incident. It did not release the nationality of the victim.

It is unclear whether the suspect was a member of the Afghan National Army or just wearing the uniform as a disguise. No group has claimed responsibility for the attack.

In recent months, there have been several high-profile incidents of men wearing Afghan army uniforms attacking NATO and Afghan positions.

In June, the Taliban launched a brazen assault on a police station near the presidential palace in Kabul, killing nine people. At least one of the attackers wore an Afghan army uniform.

In May, an individual wearing an Afghan army uniform shot dead a NATO service member in southern Afghanistan.

While not all these types of incidents during the nearly 10-year war have been carried out by the Taliban, analysts say the attacks damage trust between the U.S.-led coalition soldiers and their Afghan counterparts. In many cases, coalition soldiers are responsible for training their Afghan partners and are in close proximity to them across the country.