Updated

Fighting erupted Sunday on the outskirts of the last remaining stronghold of Somalia's militant Islamic movement, as thousands of residents streamed from the area ahead of the feared battle with Ethiopian-backed government troops.

Prime Minister Ali Mohamed Gedi said the militants in the coastal city of Kismayo were sheltering three men wanted in the 1998 bombings of U.S. embassies in Kenya and Tanzania that killed more than 250 people.

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

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The fighting broke out in Helashid, 11 miles northwest of the southern town of Jilib, the gateway to Kismayo, where an estimated 3,000 hardcore fighters were preparing for a bloody showdown.

"I can hear artillery and heavy weapons being fired outside of town," said Abdi Malik, a charity worker in Jilib, told The Associated Press by telephone.

Ethiopian MiG fighter jets were also buzzing Kismayo, an AP reporter said.

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

"My fighters will defeat the Ethiopians forces," Sheik Ahmed Mohamed Islan, the head of the Islamic movement in the Kismayo region told The Associated Press.

"Even if we are defeated we will start an insurgency. We will kill every Somali that supports the government and Ethiopians."

Mohamed Suldan Ali, a resident of Jilib, said the Islamic forces had littered the approach to the town with remote-controlled land mines. Another resident said the fighters had destroyed three approach bridges to the town.

Up to 2,000 people fled, carrying what they could. "I don't know where to go we are terrified because we can hear the fighting," said Howo Nor, a mother of three.

Many were headed for the Kenyan border.

In the past 10 days, the Islamic group has been forced from the capital, Mogadishu, and other key towns in the face of attacks led by Ethiopia, the region's greatest military power.

The U.S. government has a counterterrorism task force based in neighboring Djibouti and has been training Kenyan and Ethiopian forces. The U.S. Navy's Fifth Fleet also has a maritime task force patrolling international waters off Somalia. It will prevent terrorists from launching an "attack or to transport personnel, weapons or other material," Commander Kevin Aandahl, spokesman for the Fifth Fleet, told the AP.

Gedi said he spoke Sunday to the U.S. ambassador in Kenya, Michael Ranneberger, about sealing the Kenyan border with Somalia to prevent the three Al Qaeda suspects — Comorian Fazul Abdullah Mohammed, Kenyan Saleh Ali Saleh Nabhan and Abu Taha al-Sudani, a Sudanese — from fleeing.

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

"We would like to capture or kill these guys at any cost," Gedi told the AP. "They are the root of the problem."

Islamic movement leaders deny Al Qaeda links, but in a recorded message posted on the Internet on Saturday, deputy Al Qaeda leader Ayman al-Zawahri called on Somalia's Muslims and other Muslims worldwide to continue the fight against "infidels and crusaders."

Gedi accused al-Zawahri of trying to destabilize Somalia and its neighbors.

In Kenya, diplomatic efforts were under way to secure a peaceful end to the 12-day conflict.

Ibrahim Hassan Adow, the Islamic group's foreign affairs chief, is in the Kenyan capital, Nairobi, for talks, Islamic officials said on condition of anonymity because they were not authorized to speak to media.

The speaker of the transitional government's parliament, Sheik Sharif Hassan Aden, who has close sympathies with the Islamic group, also is in Kenya for talks.

The military advance marked a stunning turnaround for Somalia's government, which just weeks ago could barely control one town — its base of Baidoa — while the Council of Islamic Courts controlled the capital and much of southern Somalia.

The Council of Islamic Courts, the umbrella group for the Islamic movement that ruled Mogadishu for six months, wants to transform Somalia into a strict Islamic state,

Mohamed Qanyare Afrah, a former Mogadishu warlord who led the U.S.-backed alliance that was driven from the capital in June, said he believes that government control of the capital is an illusion and that Islamic fighters are ready to launch "urban guerrilla warfare."

Late Saturday, an explosion in the capital left one woman dead and two others wounded.

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