Mogadishu , Somalia ( CNN ) -- A car bomb explosion near the airport in the Somali capital , Mogadishu , killed two people and wounded four more Thursday , police Capt . Mohamed Hussein said . Those killed were civilians , and four security guards were wounded . The blast occurred when a suicide attacker drove an explosives-laden car into two bulletproof U.N. cars and detonated it , Hussein said . The area of the attack , Mogadishu 's airport , is heavily guarded . It is considered one of the city 's safe havens . No U.N. personnel were killed or injured , a U.N. spokeswoman in Mogadishu said . Terror network Al-Shabaab , al Qaeda 's affiliate in Somalia , claimed responsibility for the attack . Spokesman Sheikh Abdiazia Abu Musab contradicted the U.N. spokeswoman and claimed that the blast killed three foreign U.N. employees . The group has been designated a terrorist organization by the United States . It hopes to turn Somalia into a fundamentalist Islamic state by force but has launched attacks in other countries , such as Kenya and Uganda , that have killed dozens . The U.S. military conducted an airstrike in southern Somalia in late January against a suspected militant leader , a U.S. military official told CNN then . It is unclear if that leader was killed . On Wednesday , eight mortar rounds rained down on Mogadishu , security officials and witnesses said . No group has yet claimed responsibility for that attack .
Four others were wounded in the attack , officials say . Al-Shabaab claims responsibility for the attack . Mortar rounds fired on Mogadishu Wednesday , authorities say .