A car bomb has exploded in the Somali capital Mogadishu, killing one person and injuring one other.

Al-Shabab told Al Jazeera they had claimed responsibilty for the attack, which they said targeted Mukhtar Dheere, an immigration official at Mogadishu's international airport who they said had died. 

"We believe that the bomb was attached to the car," police officer Ahmed Siyad told the AFP news agency on Sunday.

The blast on Maka al-Mukarama, one of the seaside capital's busiest central roads, set the car on fire.

The road leads to the city's government district. The identity of the person injured is still unknown.

Witnesses said the blast could be heard several streets away.

"The car burned up into flames, there were two people with their bodies covered in blood, it was horrible," Muhsin Adan, a witness told AFP.

Al-Shabab fighters have stepped up attacks in the capital and elsewhere in the country after being chased from key cities by African Union-led troops.

Source: Al Jazeera and agencies