Several women and children were killed in the mortar attack on the military base, thought to have been carried out by Taliban militants.
The area, in the eastern province of Kunar near the border with Pakistan, is the site of frequent clashes between U.S.-led troops and Taliban militants.
In Kabul, a suicide bomber detonated a car packed with explosives, killing two soldiers and wounding several others at a checkpoint outside the military wing of Kabul international airport.
A spokesman for German forces in Afghanistan said the bomber made an initial failed attempt on two vehicles carrying German troops, but the explosives failed to detonate. The bomber later set off the blast near the airport gate.
An Afghan airport official said civilian flights to and from the airport continued as normal.
(compiled from agency reports)