Saturday, 18 August 2012 11:55
Last Updated on Saturday, 18 August 2012 12:44
An Afghan policeman on Friday shot and killed two US soldiers in western Farah province.
A member of the Afghan Local Police was responsible for the deaths, according to provincial spokesman Abdul Rahman. The attacker struck during a training exercise on an Afghan base.
Isaf confirmed in a statement that an "insider attacked" had taken place.
"Officials are investigating the incident to determine the facts and as more information becomes available it will be released as appropriate," the statement said.
This was not the only so-called "green-on-blue" attack to take place on Friday. A few hours later in Kandahar province an Afghan solider wounded two Isaf service members.
A total of nine US soldiers have been killed by their Afghan allies in the past two weeks, according to the AP.
US defence secretary Leon Panetta announced on Tuesday that the US is expanding the number of counterintelligence personnel in Afghanistan after the recent jump in insider attacks by members of the Afghan security forces.
Mr Panetta said he was deeply concerned by the killings "because of the lives lost and because of the potential damage to our partnership efforts."
General Martin Dempsey, Chairman of the US Joint Chiefs of Staff, added the US military is boosting counterintelligence expertise at battalion level and above in Afghanistan
Insider attacks have risen sharply this year to 29, up from 11 in 2011, according to the AP.
It is too early to tell what is behind this increase in attacks, Isaf says. However, likely explanations are Taliban infiltration of Afghan security forces, or a breakdown in relations between Afghan and US troops.
Either way, the attacks are badly damaging morale, experts say.