Three international soldiers have been killed in a possible insider attack in eastern Afghanistan, officials from the Nato-led force say, BBC News reported.

A man wearing Afghan army uniform was said to have opened fire on soldiers in Paktika province, close to the border with Pakistan.

Isaf forces have taken a series of measures to try to halt such attacks.

An Italian soldier died in a separate attack in Farah province in the west of the country, Italian officials said.

There was a spate of insider attacks on foreign troops last year but the last was more than a month ago, the BBC's David Loyn reports from Kabul.

Coalition forces train, mentor and fight alongside Afghan soldiers and that makes them vulnerable, our correspondent says.

In the incident close to the Pakistan border, Afghan sources told the BBC that when the man in Afghan army uniform opened fire, other international troops fired back.

The nationality of the three soldiers killed has not been confirmed. Most of the foreign troops in that area are Americans.