Witnesses said the shelling wounded at least five people. A presidential aide told Reuters that Yusuf was safe and the mortars did not land anywhere near his private quarters.

"Five mortars were fired at the president's house, one of them landed outside the gate of the palace wounding two women and three men," witness Abdulahi Mohamed told Reuters by phone.

"Another fell inside while others exploded at the corners of the palace."

Yusuf's interim government and its Ethiopian military allies are battling gunmen loyal to an Islamist movement that ruled Mogadishu and much of southern Somalia for six months in 2006, before being ousted by the allied forces.

Residents in the coastal capital say the violence has worsened in recent weeks with increased insurgent attacks against military positions and police stations.

A presidential spokesman blamed Saturday's shelling on the al-Shabab military wing of the sharia courts group.

Residents said insurgents killed an official in north Mogadishu late on Saturday and hurled a grenade at a cinema in Hodan district in the south.

"Four men armed with pistols shot dead Banadir's regional director-general for public affairs while leaving a mosque in Yaqshid on Saturday evening," Yaqshid district chair Muhidin Hassan Jusus told Reuters by phone.

Suspected insurgents were blamed for a grenade attack on a cinema that killed a young boy and forced others to scatter as they were watching an English soccer match, witnesses said.

"The gunmen entered the cinema after the blast and began destroying the television equipment. Insurgents warmed the cinema owners twice last week to close down the cinema," witness Shafi Abdulahi told Reuters.

"We were watching an exciting football game between Manchester United and Arsenal. I have never been scared like last night. I've decided not to go to a cinema ever again."