Islamic militiamen have taken key points in Somalia's capital, Mogadishu, as fighting intensifies with their rivals, a secular grouping of warlords.
Gunmen have controlled Mogadishu for 15 years
Militiamen loyal to the Islamic Courts have isolated the warlords in the north and south of the city in fighting that claimed at least 30 lives on Thursday.
The latest upsurge in violence comes despite a truce agreement between the two groups 10 days ago.
More than 140 people died in eight days of fighting earlier this month.
The Islamic Courts grouping has gradually been gaining the upper hand. Civilians have been hiding in their homes or fleeing the fighting.
Its fighters have now cut the north-south road along the coast, taking a key crossroads known as K4 and an important nearby hotel, the Sahafi.
In earlier fighting the Islamic Courts also took an airstrip north of the capital and a road to the port.
This has left the warlords of the Anti-Terrorism Alliance with only a small pocket of support in the centre of the city, correspondents say.
In the latest fighting, the two sides pounded each other with heavy machine-gun fire, rockets, artillery and mortars as fighting spread from the north of the city to the south.
"There are so many people dead, I saw nearly 30 dead and over 40 wounded," K4 resident Abdifatah Abdikadir told Reuters news agency.
"People are being carried on wheelbarrows to the hospital with broken limbs and gunshot wounds. It's going from bad to worse."
Anti-Terrorism Alliance member Ibrahim Maalim told Reuters: "The fighting is very heavy... I have never seen such a heavy exchange. Mogadishu is blazing with fire."
Much of the fighting on Wednesday was around the CC neighbourhood in north Mogadishu.
Despite the truce brokered by local elders on 14 May both sides had amassed troops there, believing they had a right to control the area.
Elders said they had tried to contact commanders with a view to a new truce but reported neither side willing to relent.
The Anti-Terrorism Alliance includes eight warlords, among them four ministers in the current government.
Correspondents say the fighting has been fuelled by a belief that the US is backing the warlords.
The US merely says it will support those trying to stop "terrorists" setting up but stresses its commitment to the country's transitional government, which functions from Baidoa, 250km (155 miles) north-west of the capital.
Somalia has had no full government since the overthrow of President Siad Barre in 1991 but this year's clashes have been the worst in the capital for more than a decade.
Several ministers involved in the fighting are reported to have resigned from the transitional government, saying that others in the administration had not been doing enough to stem the unrest.
Reports say their resignations came as they failed to meet a government ultimatum to join the rest of the ministers in Baidoa.
But Security Minister Mohammed Qanyare Afrah later denied he had resigned.