A member of the Afghan Special Forces turned his weapons Saturday on U.S. military personnel during a training exercise in northern Afghanistan, killing a local partner and injuring seven Americans.
NATO's Resolute Support Mission said an Afghan soldier also was among the wounded.
The "insider attack" occurred at an Afghan National Army regional base, Camp Shaheen, in Mazar-i-Sharif. A U.S. soldier reportedly engaged and gunned down the assailant before wounded Americans were evacuated for treatment.
The Taliban did not claim any association with the attacker but did praise him, saying he would be remembered "as a hero."
In a similar attack June 10 in eastern Nangarhar province, an Afghan commando opened fire on U.S. soldiers, killing three of them before he was gunned down by retaliatory fire.
The Taliban took credit for that attack, claiming the assailant was one of its fighters who had infiltrated Afghan army ranks.
The military base where Saturday's shooting took place was the scene of a coordinated Taliban gun-and-bomb raid in April that killed more than 150 soldiers and wounded many more, the deadliest assault on Afghan forces since 2001.
A senior international diplomat in Afghanistan said authorities are looking into the possibility that the June 10 killings in Nangarhar might be related to the earlier deaths of two Afghan policemen in what the U.S. called a 'friendly fire incident" in Helmand province. The U.S. has apologized for that incident.
Helmand is Afghanistan’s largest province, and most of it is under the control or influence of the Taliban.
A group of roughly 300 U.S. Marines arrived in Helmand in April to support struggling Afghan forces in their battle against the Taliban.
The insurgents have extended their control over swaths of Afghanistan and killed scores of Afghan security forces members since launching their so-called yearly spring offensive in late April.
The wartorn nation -- and its capital city, Kabul, in particular -- has also been hit in recent weeks by suicide bombings that have caused unprecedented civilian casualties.