A U.S. official says a U.S. soldier was killed in a firefight between Afghan and NATO troops that injured at least two other U.S. soldiers in the eastern province of Nangarhar.
The official in Washington spoke on condition of anonymity because he wasn't authorized to speak before the official announcement was released.
An earlier NATO statement said one NATO coalition soldier was killed, without revealing the dead soldier's nationality.
But Nangarhar police identified the coalition soldiers involved in the April 8 incident as Americans.
Nangarhar police chief Fazel Ahmad Sherzad said an Afghan soldier opened fire on U.S. troops, causing casualties.
Sherzad said the attacker was shot dead and two Afghan soldiers were wounded.
He said the shooting took place after a meeting between provincial governors and a senior U.S. Embassy official in the compound of Nangarhar's governor in the provincial capital, Jalalabad.
He said the Afghan soldier opened fire after the meeting ended and the U.S. and Afghan officials, including governors of Nangarhar, Konar, and Laghman provinces, left the compound.
The U.S. soldiers, who are part of NATO's Resolute Support mission, had been leaving the venue to return to Camp Gamberi in east Afghanistan, where they were stationed.
The troops were accompanied by 10 Afghan soldiers.
The U.S. Embassy said in a statement it was "aware that there was an exchange of gunfire involving Resolute Support service members" in Jalalabad.
The motive of the attack was not immediately known.
Slowing Drawdown Amid Instability
In January, an Afghan soldier killed three U.S. contractors in a similar insider attack.
NATO's combat mission in Afghanistan formally ended in December 2014 and most of the international troops have left the country.
The new NATO-led mission, Resolute Support, launched on January 1, is focused on training Afghan security forces.
The mission involves some 12,000 troops, including 9,800 U.S. soldiers.
President Barack Obama has said the United States will keep the current level of U.S. forces in Afghanistan by the end of 2015, and that the last U.S. troops will leave Afghanistan at the end of 2016.
Obama made the announcement last month during Afghan President Ashraf Ghani's visit to Washington.
Ghani, who took office in September, is still struggling to form a cabinet.
Ghani's latest choice for defense minister dropped out on April 8, just two days after being nominated for the job.
General Afzal Ludin said his nomination had caused internal turmoil and he feared it could be divisive.
Ludin, a former Soviet-era commander, was the second to be nominated for the defense post after the cabinet rejected the first in January.
Ghani and his former political rival, chief executive Abdullah Abdullah, who formed a unity government in September, have only eight ministerial appointments.
The delay is stifling the economy and is demoralizing the country's security forces as they battle the Taliban largely alone, following the withdrawal of foreign combat troops.