Somali government troops backed by Ethiopian tanks and fighter jets captured the last major stronghold of a militant Islamic movement Monday, while hundreds of Islamic fighters — many of them Arabs and South Asians — fled the town.

To cheering and waving crowds, well-armed troops drove into Kismayo after clearing roads laced with land mines that had been left by an estimated 3,000 hard-line Islamic fighters fleeing a 13-day military onslaught by government troops backed by Ethiopian tanks and MiG fighter jets.

"We have entered and captured the city," Maj. Gen. Ahmed Musa told The Associated Press while riding aboard a truck into Kismayo, where the Islamic fighters had vowed to make a last stand but melted away under artillery fire.

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Hundreds of gunmen, who apparently deserted from the Islamic movement, began looting warehouses where the Council of Islamic Courts had stored supplies, including weapons and ammunition.

Gangs skirmished in the streets, and the southern coastal city was descending into chaos, said Sheik Musa Salad, a local businessman.

"Everything is out of control, everyone has a gun, and gangs are looting everything now that the Islamists have left," he said.

Prime Minister Ali Mohamed Gedi offered amnesty to hundreds of Islamic fighters if they gave themselves up, but he made no such offer to leaders of the group. He also ordered a countrywide disarmament starting Tuesday, an immense task in Somalia, which is awash with weapons after a 15-year civil war.

"The warlord era in Somalia is now over," Gedi said at a news conference in the recently captured capital, Mogadishu, giving a three-day deadline to hand over all weapons.

Among those sought were three Al Qaeda suspects wanted in the 1998 bombings of U.S. embassies who were being sheltered by the Islamic group. The government hoped to catch them before they slipped out of the country.

Gedi also appealed for humanitarian aid and he repeated calls for an African Union peacekeeping force.

Maj. Felix Kulayigye, a spokesman for Uganda's army, said 1,000 troops could be ready to deploy in a few days. "We have one battalion prepared to go to Somalia immediately after they are cleared by the ministry of foreign affairs," he said.

A group of seven regional countries, known as IGAD, proposed a peacekeeping force for Somalia two years ago, and the United Nations endorsed the peacekeeping plans last month, but fighting prevented a deployment.

At the Somali government headquarters in Baidoa, government spokesman Abdirahman Dinari told the AP that Uganda and Nigeria have agreed to send a total of 8,000 troops soon. Dinari said the government had also asked the United States to provide air and sea surveillance to prevent suspected extremists from escaping.

The Islamic forces have a base near the Kenyan border on a small peninsula called Ras Kamboni, where there is a pier and traditional oceangoing boats known as dhows. Ethiopian MiG fighter jets flew low, looking for boats carrying escaping Islamic fighters.

Meanwhile, senior Western diplomats were pushing for the deployment of an African-led peacekeeping force in Somalia as soon as possible to help stabilize the country, said a U.S. government official on condition of anonymity because the official was not authorized to speak to the media.

Kenyan President Mwai Kibaki, in his New Year's message, called for an urgent IGAD summit to discus the Somali crisis.

The Islamic forces began to disintegrate after a night of artillery attacks at the front line and following a mutiny within its ranks, witnesses said.

Islamic leaders had vowed to make a stand against Ethiopia, which has one of the largest armies in Africa, or to begin an Iraq-style guerrilla war.

"Even if we are defeated we will start an insurgency," said Sheik Ahmed Mohamed Islan, the head of the Islamic movement in the Kismayo region. "We will kill every Somali that supports the government and Ethiopians."

Somalia's interim government and its Ethiopian allies have long accused Islamic militias of harboring Al Qaeda — an accusation the movement denies — and the U.S. government has said the 1998 bombers have become leaders in the Islamic movement in Africa.

"If we capture them alive, we will hand them over to the United States," Gedi told the AP.

The military advance marked a stunning turnaround for Somalia's government, which just weeks ago could barely control one town — its base of Baidoa. The Council of Islamic Courts, which wants to transform Somalia into a strict Islamic state, had held the capital and much of southern Somalia.

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