The cause of Tuesday's fire wasn't known and no one was injured. There were no immediate indications that the blaze was the result of enemy fire, said U.S. military spokeswoman Capt. Alayne Cramer.
The military was investigating the origins of two explosions that rattled the area outside a U.S. military compound in northern Kunduz province late Tuesday. No one was hurt in the blasts.
Meanwhile, a lone gunman opened fire on U.S. Special Forces in Urgun in eastern Afghanistan, Cramer said. No one was hurt, but Urgun has been a particularly tense area for special forces operating there, who have faced regular attacks. Usually the gunmen, who operate in small groups, flee the area, often into neighboring Pakistan.
There have been reports from former Taliban that fresh training camps have been set up in the mountainous Urgun area of Paktika province. The camps are small and mobile, they say. The United Nations also confirmed reports of new training camps in eastern Afghanistan.