Two NATO soldiers were wounded, and an Afghan National Army soldier was killed, during a clash inside a military base in Kabul today. NATO and Afghan authorities are investigating the incident, which appears to be the fifth green-on-blue, or insider attack, recorded in Afghanistan in the past five weeks.

The attack took place inside a base on the outskirts of Kabul, the Afghan capital, according to Reuters. Afghan Defense Ministry spokesman Dawlat Waziri said that “[t]here was an argument between an Afghan and foreign soldier inside a military base… where they opened fire on each other. An investigation is ongoing.”

The BBC reported that the Afghan soldier was killed following an altercation in which he had begun shooting at the NATO soldiers, injuring at least one of them. The Reuters report said “a number of other soldiers” were injured, but did not indicate whether they were Afghan or NATO troops.

Spate of recent attacks

Today’s attack is the fifth since Sept. 21, when an Afghan National Army soldier opened fire on US special forces near Gardez in Paktia province, killing three and wounding one more before being shot by US forces in return fire [see LWJ report, Afghan soldier kills 3 ISAF special forces troops in Paktia].

Less than a week later, on Sept. 26, an Afghan National Army soldier at a military training base in the Gerda Serai district in Paktia province opened fire on a US soldier, killing one and wounding several others [see Threat Matrix report, Another green-on-blue attack in Paktia]. The gunman was killed immediately after the attack. The attack was quickly claimed by the Taliban in a text message.

On Oct. 5, an “alleged contracted security guard” gunned down an ISAF soldier on a base in Zabul province [see LWJ report, Senior ISAF member killed in green-on-blue attack in southern Afghanistan].

And on Oct. 13, a member of the Afghan National Security Forces shot two US soldiers in Sharana city, the capital of Paktika province. One US soldier was killed and the other wounded; the attacker escaped following the attack [see LWJ report, ISAF soldier killed in latest insider attack in eastern Afghanistan].

According to The Long War Journal‘s statistics, today’s green-on-blue attack is the 13th so far this year; 14 ISAF soldiers have been killed in the 13 attacks.

Since Jan. 1, 2008, there have been a total of 85 attacks, resulting in the deaths of 140 Coalition personnel and the wounding of 159 more. Deaths from insider attacks so far this year amount to nearly 10% of total Coalition casualties, down from a high of 15% last year, but significantly higher than the 6% in 2011. For more information, see LWJ special report, Green-on-blue attacks in Afghanistan: the data.

The relative downturn is likely due to the introduction of security measures in 2012 such as the use of “guardian angel” soldiers to overwatch US troops, and to reduced partnering between Afghan and Coalition forces as the drawdown continues. From a peak of level of about 101,000 soldiers in 2011, the US troop presence in Afghanistan had been reduced to 63,000 by July, and that number is expected to drop to 34,000 by February 2014. On June 18, overall security responsibility for Afghanistan was officially transferred to Afghan forces.

Green-on-blue data remains “classified” by ISAF

While 13 green-on-blue attacks have been reported so far this year by The Long War Journal, the likelihood is that the number is much higher. ISAF has not disclosed the overall number of green-on-blue incidents in which ISAF soldiers were wounded by Afghan security personnel, or the attacks on ISAF personnel that did not result in casualties.

ISAF told The Long War Journal in March 2012 that “these statistics … [are ] … classified.”

“[A]ttacks by ANSF on Coalition Forces … either resulting in non-injury, injury or death … these stats as a whole (the total # attacks) are what is classified and not releasable,” Lieutenant Colonel Jimmie Cummings, ISAF’s former Press Desk Chief, told The Long War Journal. Cummings said that ISAF is “looking to declassify this number.”

Inquiries as to why the overall statistic is classified went unanswered. More than one and a half years later, the data remains classified.

Many green-on-blue attacks remain unreported. For instance, one such attack, on March 25 in Kandahar province, is known only because a reporter from The Long War Journal was present when the incident took place. In that attack, Afghan local policemen opened fire on a US base after US personnel tried to arrest a known Taliban commander at the ALP checkpoint [see LWJ report, The anatomy of green-on-blue tensions in Panjwai].

Insider attacks a key part of Taliban strategy

The Taliban claim to have stepped up their efforts to infiltrate Afghan security forces as well as “lure” and encourage Afghan security personnel to attack ISAF troops and advisers.

In October 2012, Taliban emir Mullah Omar released an Eid al-Adha message that urged followers to “[i]increase Increase your efforts to expand the area of infiltration in the ranks of the enemy and to bring about better order and array in the work.” The statement continued: “We call on the Afghans who still stand with the stooge regime to turn to full-fledged cooperation with their Mujahid people like courageous persons in order to protect national interests and to complete independence of the country. Jihadic activities inside the circle of the State militias are the most effective stratagem. Its dimension will see further expansion, organization and efficiency if God willing.”

Omar had previously addressed the issue of green-on-blue attacks at length in a statement released on Aug. 16, 2012. Omar claimed that the Taliban “cleverly infiltrated in the ranks of the enemy according to the plan given to them last year,” and urged government officials and security personnel to defect and join the Taliban as a matter of religious duty. He also noted that the Taliban have created the “Call and Guidance, Luring and Integration” department, “with branches … now operational all over the country,” to encourage defections. [See Threat Matrix report, Mullah Omar addresses green-on-blue attacks.]

At the end of April, the Taliban announced that green-on-blue attacks would be a key part of this year’s strategy.

“This year’s spring operation, in accordance with its combat nature, will consist of special military tactics quantity and quality wise while successful insider attacks, to eliminate foreign invaders, will be carried out by infiltrating Mujahideen inside enemy bases in a systematic and coordinated manner,” the Taliban announced on April 27.

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