kabul suicide bomber afghan capital kabul kill many eight people wound many others appear workers leave offices start even rush hour witness officials say tuesday islamic state claim responsibility attack wazir akbar khan heavily fortify area city house numerous foreign embassies government build reuters television team count eight people appear kill besides several wound scene shroud smoke explosion casualties appear afghan civilians public health official say three dead 15 wound take city hospitals security official speak condition anonymity say least seven people kill 21 wound scene attack cover smoke dust saw seven eight vehicles load dead injure people come area say ali nazari manager nearby travel agency explosion come time heighten security kabul follow series attack october include one shi ite mosque city kill 50 people separate attack army train facility kill least 15 soldier security already step considerably follow devastate truck bomb attack outside german embassy may 31 kill least 150 people series barriers checkpoints across central area city kabul police spokesman say blast appear cause suicide bomber foot target attack immediately clear well foreign embassies area contain defense ministry department deal foreign relations several private businesses include barber travel agency afghan western security officials say recent days expect attack kabul response pressure exert taliban insurgent group increase u.s. air strike recent months u.s. step campaign air strike part new strategy aim reverse gain make taliban force insurgents seek peace talk afghan government western officials say campaign inflict significant casualties taliban fighters provinces say battlefield losses may push insurgents attack kabul high profile target blast hit afghan capital kabul numerous casualties