An explosion rocks central Kabul anda thick plume of black smoke canbeseen rising from the vicinity of the sprawling USembassy inthe Afghan capital, reports say.
Warningsirens were sounded Tuesdayatthe embassy compound, whichis also close to NATO headquarters in Afghanistan.
An Afghan official saida possible bomber carried out theattack whichwas followed by gunfire and claimed by the Taliban.
Afghan Interior Ministry Sediq Sediqqi said the area has been surrounded by security forces and there are fears of casualties.
Taliban militants have stepped up their attacks against foreign troops and Afghan security forces since announcing the start of their spring offensive last week.