There are no more hospital beds available in this bloodstained capital, and barely enough bandages to patch up the wounded. Even the bottles of medicine are running dry.

But still the patients keep pouring in — and they are the lucky ones, having survived another day of gunfire and mortar shells as Islamic insurgents battle troops allied to Somalia's fragile government.

"Even the shades of the trees are occupied at this point," Dahir Dhere, director of Medina Hospital, the largest health facility in Mogadishu, said Monday. "We are overwhelmed."

Battles rocked Mogadishu for the sixth straight day Monday as Somalia heads toward one of the worst humanitarian crises in its history, with civilians getting slaughtered in the crossfire. A local human rights group put the death toll at 1,000 over just four days earlier this month, and more than 250 have been killed in the past six days.

More than 320,000 of Mogadishu's 2 million residents have fled since heavy fighting started in February.

Ahmed Mohamed, 32, was not one of them. A mortar shell hit him over the weekend, crushing his right leg.

"The doctors told me I would die unless they cut off my leg," Mohamed said, tears streaming down his face in the city's Keysaney Hospital, which was packed beyond capacity with nearly 200 people. "So I have to let them do it."

Somalia Prime Minister Ali Mohamed Gedi said Monday his interim government was winning the battle against the insurgents, but called for greater support from the international community.

"If we do not get international support the war may spread throughout the region and Africa," Gedi said. "These terrorists want to destabilize the whole region."

The government and its Ethiopian backers have been facing mounting pressure from the U.S., European Union and United Nations over the mounting civilian death toll and appear determined to bring order to the city before a planned national reconciliation conference in June.

But the fighting has decimated Mogadishu, already one of the most violent and gun-infested cities in the world. At least 18 civilians were killed Monday, said Sudan Ali Ahmed, the chairman of the Elman Human Rights Organization group. A 6-month-old baby was among those wounded, said a witness, Khadija Farah.

Somalia has been mired in chaos since 1991, when warlords overthrew dictator Mohamed Siad Barre and then turned against each other. The western city of Baidoa, where the Somali Parliament is based, was dubbed "City of Death" in the 1990s during a searing drought and famine there. Mogadishu, once a stunning seaside capital, is now a looted shantytown teeming with guns, with no functioning government or institutions.

A national government was established in 2004, but has failed to assert any real control.

Last month, troops from neighboring Ethiopia used tanks and attack helicopters to crush a growing insurgency linked to the Council of Islamic Courts. The movement had controlled Mogadishu and much of the country's south for only six months in 2006, but those were the most peaceful months since 1991.

The group was driven from power in December by Somali and Ethiopian soldiers, accompanied by U.S. special forces, who have accused the group of having ties to Al Qaida. The militants reject any secular government, and have sworn to fight until Somalia becomes an Islamic emirate.

Meanwhile, the capital and its surrounding towns have become scenes of ghastly despair. Women and children flee on foot with little more than their clothes and some cooking pots, then sleep by the side of the road. In Afgoye, about 30 kilometers (20 miles) from the capital, fights were breaking out over a spot of shade beneath a tree.

"Everyone wants to sit in the small area under the tree," said Asha Hassan Mohamed, a mother of seven who reached Afgoye last week but returned to Mogadishu because she couldn't find any food.

"It's so crowded because there is no shelter."

The United Nations said the fighting had sparked the worst humanitarian crisis in the war-ravaged country's recent history, with many of the city's residents trapped because roads out of Mogadishu were blocked.

Catherine Weibel, a spokeswoman for the U.N. refugee agency, said many of those who haven't fled the capital are simply too vulnerable to do so.

"All the people who are sick, in wheelchairs, disabled," she said, "they cannot leave."