The US-led coalition in Afghanistan says three of its troops were killed and another was wounded in a roadside blast.
In a statement, the coalition says the troops were in a vehicle that was bombed on Wednesday in western Afghanistan. It did not provide the exact location of the attack or the nationalities of the victims.
Taliban militants regularly target Afghan, US and other foreign soldiers with roadside and suicide bombs.
More than 5,200 people _ mostly militants _ have died in insurgency related violence this year, according to an Associated Press count of figures from Western and Afghan officials.