Mogadishu: Fighting raged for a second day in the Somali capital on Sunday as Ethiopian troops clashed with Islamist-led rebels in the heaviest battles for weeks.

Fearful residents cowered behind closed doors as the forces of the interim government, which is backed by Ethiopia and the United Nations, sought again to crush heavily armed insurgents.

At least 15 people have been killed so far, local media says, including as many as seven Ethiopian soldiers. Dozens of civilians have been wounded by stray bullets and shrapnel.

The fragile Somali government has been shaken by an insurgency of Iraq-style roadside bombings, assassinations and suicide attacks since it routed a hard-line Islamist movement in January with the help of Ethiopian tanks and warplanes.

The new battles with rebels, which the government says include foreign extremists linked to Al Qaida, come as tensions at the top of the fledgling administration threaten to split it wide open.