KABUL, Afghanistan - Three men wearing Afghan army uniforms and driving an Afghan army vehicle forced their way onto a U.S. base in eastern Afghanistan on Friday and opened fire, killing one civilian contractor and wounding other U.S. troops, U.S. defense officials said.
If the shooters do prove to be Afghan soldiers, it will be the second insider attack this year by Kabul's forces against their international allies. The attack happened at midday, several hours before Defense Secretary Chuck Hagel arrived in Afghanistan for his first visit as Pentagon chief.
The attack highlights the continuing dangers faced by U.S. troops even as they hand over more security duties to the Afghans ahead of the end of NATO combat operations in 2014. Nonetheless, such incidents have become less frequent since 2012, when coalition forces faced a rash of insider attacks at the rate of roughly one attack a week.
NATO spokesman Maj. Adam Wojack says all three attackers were killed in the incident at a U.S. base in the Tagab district in Kapisa province, and Afghan and NATO coalition officials are now investigating.
A second U.S. defense official said initial reports indicated three U.S. troops were wounded in the firefight. The official spoke anonymously because the investigation is ongoing. The military will not release the contractor's nationality until next of kin has been notified.
Afghan official Abdul Sabor Wafa, chief of staff for the Kapisa governor, says the attack happened at 1:30 p.m. local time, and that the attackers were not able to penetrate the base but were killed as they tried to storm the gate. Wafa said Afghan defense officials had not yet established if the men were Afghan soldiers or militants wearing stolen uniforms.
A Taliban spokesman said they did not carry out the attack, and insisted in a statement to the AP that the attackers were from the Afghan army.
If they were soldiers as opposed to disguised insurgents, then it will be only the second such attack this year - the first being in January when an Afghan soldier turned his weapon against foreign and Afghan troops, killing one British soldier.
That's a slower pace than in 2012, when coalition troops were hit with 46 "green on blue" attacks that killed 62 coalition troops and wounded 95, according to a senior coalition intelligence officer. The officer spoke on condition of anonymity because he was not authorized to speak publicly. By AP's count, at least 63 coalition troops were killed, and by this time last year, eight attacks had already happened. In 2011, 21 insider attacks killed 35.
The officer attributed the reduced number of such incidents to measures like better vetting of Afghan soldiers, and both U.S. and Afghan commanders increasing their counterintelligence resources devoted to scanning Afghan ranks for signs of discontent, among other measures.
Gen. James Mattis, the U.S. Central Command chief who oversees U.S. military operations in Afghanistan and across the greater Middle East, told a House committee on Wednesday that he is pleased to see a recent drop-off in insider attacks.
"I think I know why it's gone down," he said. "It has to do with training. It has to do with counterintelligence training we've given to the Afghans so they have ferreted out some of these people inside their ranks, and caught them. And we have very good techniques for doing that."
U.S. forces are also conducting far fewer joint operations with Afghan troops ahead of the 2014 transition, so there are fewer opportunities for the two to interact.