By LYNNE O'DONNELL and RAHIM FAIEZ
The shooting happened after Afghan provincial leaders met a U.S. Embassy official at the compound of the Nangarhar provincial governor in the city of Jalalabad. All U.S. Embassy staff were accounted for and safe, the diplomatic mission said.
"Right after the U.S. official had left, suddenly an Afghan army soldier opened fire on the U.S. soldiers who were present in the compound," said Afghan Gen. Fazel Ahmad Sherzad, the police chief for eastern Nangarhar province
The American troops returned fire, killing the Afghan soldier, whom Sherzad identified as Abdul Azim of Laghman province.
The motive for his attack was not immediately known and no group claimed responsibility for the assault. In past attacks, Taliban insurgents have been known to wear Afghan police or military uniforms to stage attacks on the international troops. Others have opened fire apparently on the own accord, like an Afghan soldier who last year killed Maj. Gen. Harold J. Greene, the highest-ranked U.S. officer to be slain in combat since 1970 in the Vietnam War.
The attack was the second fatality suffered by NATO since the beginning of the year. The last incident in which an American soldier was killed in Afghanistan was on Dec. 13, when a roadside bombing killed two U.S. troops in Parwan province. Also, an Afghan soldier killed three American contractors on Jan. 29 in another apparent insider attack.
NATO confirmed that one of its soldiers died in Wednesday's attack, without providing the nationality of the slain soldier. A Washington official confirmed the soldier was American, speaking on condition of anonymity because he wasn't authorized to release the information before an official announcement was made.
The U.S. Ambassador to Afghanistan, P. Michael McKinley, was not present at the time of the incident, Sherzad said. Neither Sherzad nor the U.S. Embassy identified the senior American diplomat at the meeting.
Information was sketchy and an eyewitness initially told The Associated Press that four U.S. troops had been wounded in the attack — not three as Sherzad said — and were being treated at a clinic on the American base in Jalalabad.
Noman Atefi, the spokesman for the Afghan National Army's eastern corps command, said one Afghan soldier had been killed and two others wounded in the shootout. It was not immediately clear if the fatality he was referring to was the attacker.
White House Press Secretary Josh Earnest, when asked about the shooting, said it "underscores that Afghanistan continues to be a dangerous place."
"We're going to continue to work closely with President (Ashraf) Ghani, other members of the Afghan government and our international partners to support the Afghan government of national unity as it pursues a future of greater peace, prosperity and, finally, an end to this conflict," Earnest said.
At the Pentagon, spokesman Col. Steve Warren said an investigation into the shooting was underway and indications suggested it was an insider attacker.
There were at least four insider attacks in Afghanistan in 2014. The worst was on Aug. 5, when the Afghan soldier shot and killed Greene and wounded 18.
Insider attacks first surged in 2012 to become a tactic in the Taliban insurgency. That year, more than 60 coalition troops — most of them Americans — were killed in more than 40 attacks that threatened to shatter all trust between U.S. forces and the Afghan troops.
Such attacks are sometimes claimed by the Taliban as proof of their infiltration. Others are attributed to personal disputes or resentment by Afghans who have soured on the yearslong international presence in their country after the fall of the Taliban's ultra-conservative Islamic regime.
In February, U.S. Gen. John F. Campbell, the commander of U.S. and NATO forces in Afghanistan, told the Senate Armed Services Committee that the U.S.-led coalition continues to "implement mitigations to avoid patterns and prevent complacency" that can lead to such insider attacks.
"These measures have reduced, but not eliminated, the threat. We will remain vigilant to prevent future insider attacks," Campbell said.
The Western-backed Afghan government's nearly 13-year war against insurgents has intensified in the wake of the pullout of foreign combat forces, as both sides seek to strengthen their positions ahead of possible peace talks.
Meanwhile, two Afghans were killed and three were wounded in an ambush late Tuesday aimed at the Afghan police in eastern Kunar province, which lies along the border with Pakistan and where the Taliban have a strong presence.
Farid Dhekhan, the spokesman for the provincial police chief, said the attack in Narang district killed a man and woman from the same family. No police officers were wounded, he said.
Associated Press writers Fred Frommer, Connie Cass and Sagar Meghani in Washington contributed to this report.
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