At least six people were killed and many more wounded Thursday in a suicide car bomb attack targeting a United Nations convoy close to the entrance of Mogadishu's heavily-fortified international airport, police and witnesses said.
Somalia's Al-Qaeda-linked Al Shabaab rebels told that one of their suicide bombers carried out the attack.
The bomb went off near a checkpoint at the entrance to the airport complex, which also houses the base of Amisom -- the African Union force fighting Al Shabaab rebels -- as well as a number of foreign diplomatic missions and United Nations offices.
Witnesses said the bomb went off near a United Nations convoy. A UN source said the convoy was carrying staff from the refugee agency UNHCR and their Somali guards. The staff were said to be "shaken" by the attack but apparently unharmed, although their guards may be among the casualties, the source said.
"At least six people, most of them civilians, died in the car bomb explosion. There are many casualties, serious injuries. We are still investigating the incident, the toll could rise anytime," another police official, Said Mohamed said.
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An Al Shabaab spokesman claimed a number of foreigners were among the dead.
"This was an operation carried out by Al Shabaab. It was a brother who took a sacrificial act to defend the people of Somalia," Al Shabaab military spokesman Sheikh Abdul Aziz Abu Musab said.
"The target was a UN convoy. According to our report, several invaders have been killed," he said.
Another witness told an AFPTV journalist at the scene that as many as 14 people may have been killed. An AFP photographer at the scene saw the burning wreckage of a vehicle and several destroyed shops.
The airport is considered to be among the safest parts of Mogadishu, and is ringed by checkpoints and large numbers of armed guards.
A number of foreign diplomatic missions are based inside the huge airport complex, which has also been used to house a number of UN staff since a city-centre UN compound was attacked by the Al Shabaab last year.
Britain's ambassador to Somalia Neil Wigan, whose embassy is within the high-security airport complex, said on Twitter that he had heard a "major explosion" that sent smoke into the air.
The attack comes amid an apparent upsurge of Al Shabaab bombings in and around Mogadishu. Earlier this week the group carried out twin bombings inside the city, targeting government officials.
The Al Shabaab once controlled most of southern and central Somalia but withdrew from fixed positions in Mogadishu two years ago.