WASHINGTON (AP) — A U.S. official says "about a dozen" of the victims of an Afghan insider attack on Tuesday were Americans, and at least one American was killed.

The official says many details of the attack early Tuesday were still unclear and the numbers could change. The official spoke on condition of anonymity because the official was not authorized to discuss details of the attack by name on the record.

A man dressed in an Afghan army uniform opened fire on foreign troops at Camp Qargha, a base west of the capital, Kabul. Among the wounded was a German brigadier general.

Gen. Mohammmad Zahir Azimi, a spokesman for Afghanistan's Defense Ministry, said a "terrorist in an army uniform" opened fire on both local and international troops. Azimi said the shooter had been killed.

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