Islamic militia vowed to turn Somalia into a religious state on Tuesday, pushing north to take more territory after winning a three-month battle for Mogadishu.
But thousands of Mogadishu residents protested against the take-over and defeated warlords said they would fight back. Clan elders warned the Islamic side against more advances.
Fighters loyal to Shariah courts seized the lawless capital on Monday from a self-styled anti-terrorism coalition of warlords widely believed to be backed by Washington.
Some 350 people, mostly civilians, have died since February in fierce fighting for Mogadishu interspersed by tense lulls. The United Nations says about 1,500 civilians were wounded in the close-quarter battles using mortars and anti-aircraft guns. It was the first time the warlords had been dislodged from Mogadishu since ousting former ruler Mohamed Siad Barre in 1991.
"Until we get the Islamic state, we will continue with the Islamic struggle in Somalia," Sheikh Sharif Ahmed, chairman of Mogadishu Islamic courts, told a rally of hundreds.
Somalia's interim prime minister, Mohamed Ali Gedi, earlier congratulated the Islamic side on their victory over warlords who many Somalis believe tried to undermine the government. The Islamic fighters advanced on Tuesday towards the warlord stronghold of Jowhar, about 90 km (56 miles) north of Mogadishu.
"Our forces are in the village of Qalimoy, 20 km south of Jowhar. We are just waiting for orders from our leaders to capture it," militia leader Siyad Mohamed, who is allied to the Islamic courts, told Reuters from Balad on the road to Jowhar.