Authorities in Afghanistan say four policemen were killed and four others wounded by militants who attacked a security checkpoint in southern Kandahar province.
Police say one militant also was killed during the assault - a drive-by shooting - late Sunday in Maywand district, west of Kandahar city.
Less than 24 hours earlier, two U.S. soldiers were wounded in an attack on their patrol in southern Zabul province.
Two weeks ago, American and Afghan forces launched a winter offensive, dubbed "Operation Lightning Freedom", to hunt for Taleban militants ahead of planned parliamentary elections next year.
The operation is aimed at strengthening security to ensure that the parliamentary election, in about four months, can be conducted as smoothly as Afghanistan's landmark presidential ballot in October.
Some information for this report provided by AFP and Reuters.