At least 10 people, most of them civilian have been killed and over 21 others injured in heavy clashes that pitted Somali rebels against the African Union peacekeeping troops across the restive Somali capital Mogadishu, reports said.

The fighting erupted in the capital's Dhargkenley, Wardhigley, Hodan and areas surrounding the presidential palace Villa Somalia, where rebel fighters launched overnight offensive against the government troops backed by AU soldiers.

According to witnesses, the fighting was intense and both sides used heavy weapons while sporadic could still be heard in the early Friday morning hours.

Al-Shabaab insurgents claimed responsibility of the clashes, admitting that it has lost three of its fighters in the battle.

AU forces are yet to comment about the latest clashes which come at the wake of reportedly government-planned offensives in the war-torn capital.

However, AU force sokpesman Barigye Bahuko says that the peacekeeping forces are unable to maintain the security of the entire city due to small number of the troops and lack of better equipments.