Unknown assailants fired mortars at the presidential palace in the Somalia capital Mogadishu overnight. The African Union (AU) said the attack shows the need for peacekeepers to move quickly into the Horn of Africa nation. Five mortars slammed into Somalia's presidential palace on Friday (January 19) night and gunfire rattled across Mogadishu in the latest violence in chaotic Somalia, witnesses and officials said. A senior government source told Reuters that eight mortar shells were fired at Villa Somalia but only five hit the presidential palace. The other three went into nearby houses. After the mortar attacks, assailants with machineguns ran towards the building where they fought presidential guards around the hilltop compound for about 20 minutes before retreating, witnesses said. Suspicion fell immediately on Somali Islamists, who controlled most of the south until an offensive by the government and allied Ethiopian troops over Christmas and the New Year drove them out of Mogadishu. Now scattered to remote parts of the south near the border with Kenya, the Islamists have vowed a guerrilla war. Yusuf arrived in the city days ago to take up residence in the bullet and mortar-scarred building that used to house former dictator Mohamed Siad Barre, whose ouster by warlords in 1991 ushered in the last 16 years of anarchy in the Horn of Africa nation. It was not yet known if the 72-year-old Yusuf or any other of the occupants were hurt during the attack. As the attack began after dark, more than a dozen explosions boomed across Mogadishu and gunfire cracked out to break a lull in violence of several days in the war-scarred capital, a Reuters witness said. "Last night at about 8.40 in the evening we heard mortars near us, we don't know of any injures or deaths but there were at least was six mortars, after that these was a heavy exchange of gunfire," said a local resident, Abdirahman Mohamed Hassan. Ethiopian troops, who helped the Somali interim government drive the Islamists out of Mogadishu, have in past days been the target of attacks. The Islamists regard the Ethiopians as illegitimate occupiers. A Somali government bodyguard reached by telephone said Friday night's attack was launched from a school just a few blocks north of the white-washed presidential compound. The attack on the presidential palace has shown the need for peacekeepers to move quickly into the Horn of Africa nation, the African Union (AU) said after endorsing such a mission. The AU's peace and security council approved a 7,650-strong force for Somalia late on Friday (January 19), just minutes before attackers struck Mogadishu's hilltop Villa Somalia. Many doubt the AU's capacity to muster such a force, let alone tame Somalia. It has been in chaos since the 1991 ousting of a dictator and defied U.S. and U.N. peacekeepers in the early 1990s in a mission shown in the "Black Hawk Down" film. Only Uganda has publicly vowed to supply troops. But Djinnit said a second, unnamed country had also pledged to contribute, meaning the first three of nine planned 850-soldier AU battalions could go in "within weeks". The AU, whose peacekeepers in Sudan's Darfur region have failed to halt the conflict there, wants the United Nations to take over after six months. But it is not at all clear whether the world body's members want to take on such a mission.