In Afghanistan’s first green-on-blue attack since September, a female Afghan officer has shot and killed a US military adviser outside Kabul’s police headquarters, a senior police official said. NATO soures have confirmed the Kabul shooting death.

An investigation into the shooting is underway, Interior Ministry spokesperson Sediq Seidiqqi said in an interview with AFP. The shooter was detained by her fellow officers after the incident, Sidiqqi added. Afghan and ISAF officials are reportedly working to confirm that the woman is a police officer.

The dead adviser was a contractor whose name and nationality are being withheld, NATO command spokesperson US Air Force Lt. Col. Lester T. Carroll told AP.

It is currently unclear if the contractor’s death was intentional or accidental, deputy Police Chief Mohammad Daoud Amin said.

The shooting came just hours after an Afghan police officer opened fire on five colleagues at a checkpoint in the country's north. The attacker then stole their weapons, and fled to join the Taliban, the local deputy provincial governor said.

In mid-September, three similar attacks took place in Afghanistan over a single weekend, killing eight NATO troops.

More than 60 coalition troops were killed in Afghanistan in 2012, a dramatic increase from the 35 killed last year. The violence comes ahead of the coalition’s planned pullout in 2014.

fghan policemen stand guard at the entrance to police headquarters in Kabul on December 24, 2012 (AFP Photo / Shah Marai)

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