A suicide car bomber killed six civilians Thursday in an attack on a convoy of U.S. troops near the airport in the Afghan capital, Kabul.
At least 37 other people were injured - among them four U.S. soldiers who were traveling in the two-vehicle convoy.
Taliban militants claimed responsibility for the attack.
Also today, the Pakistani government lodged a strong protest against coalition forces in Afghanistan after a cross-border attack killed two women and two children in Pakistan.
A coalition spokesman, Major Chris Belcher, confirmed that U.S.-led forces fired precision-guided ammunition into Pakistan Wednesday. He said the cross-border fire was aimed at a militant compound inside Pakistan.
Separately, Afghan officials say a roadside bomb killed three Afghan police and wounded four others today in Wardak province, southwest of Kabul.
In the southwestern province of Nimroz, the provincial governor said air strikes by Afghan and international forces have killed 41 Taliban militants in the area this week.
Some information for this report was provided by AFP, AP and Reuters.