The U.S. military in Afghanistan says a bomb explosion has killed four American service members.
The troops were on patrol in central Uruzgan province Monday, when their vehicle struck the explosive device.
Meanwhile, in Kunar province bordering Pakistan, an Afghan soldier was killed and five others wounded when their vehicle hit a land mine.
Late Sunday, in southern Helmand province, Taleban insurgents ambushed an Afghan militia unit, killing two men and leaving six missing.
A purported spokesman for the Taleban said the missing militiamen were killed, but Afghan authorities confirm only two deaths.
In another violence late Sunday, on a highway between Kandahar and Herat, suspected Taleban set fire to a tanker supplying fuel to coalition forces.
Some information for this report was provided by AP and Reuters.