At least one Afghan soldier was killed and seven American soldiers were wounded in an incident at a base in northern Afghanistan on Saturday, a US military official said.
A spokesman for the US military command in Kabul said earlier comments by an Afghan official that Americans had been killed were incorrect.
But he confirmed that seven soldiers had been evacuated after being wounded in the incident at Camp Shaheen, the headquarters of the Afghan army's 209th Corps in the northern city of Mazar-i-Sharif.
At least one Afghan soldier was killed and another wounded, the official said.