Updated

Government troops backed by Ethiopian soldiers were fighting about 600 Islamic militiamen in the southern tip of Somalia, an official spokesman said Thursday.

In the past 10 days, Ethiopian-backed government forces have driven out the Islamic movement that had controlled Mogadishu and much of southern Somalia for more than six months. The Islamic movement retreated to the southern tip of Somalia and vowed to keep fighting, raising the specter of an Iraq-style guerrilla war.

The Somali forces have surrounded the Islamic militiamen "from every direction" in the southwestern district of Badade, near the Kenyan border, government spokesman Abdirahman Dinari told The Associated Press. "The fighting is going on," Dinari said. "We hope they will either surrender or be killed by our troops."

Kenya sent extra troops to the Somali frontier and closed its border, fearing an exodus of refugees and foreign fighters.

Dinari said some Islamic militants have been trying to escape by sea. "But U.S. anti-terrorist forces have been deployed there to prevent them from escaping," he added.

In Washington on Wednesday, State Department spokesman Sean McCormack said U.S. Navy vessels were deployed off the Somali coast looking for Al Qaeda and allied militants trying to escape.

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Dinari said the government believes foreign terrorist elements are among the Islamic militiamen fighting in Badade.

With the Islamic movement's fighters on the run, concern has grown about extremists believed to be among them. Three Al Qaeda suspects in the 1998 bombings of U.S. embassies in East Africa are believed to be leaders of the Islamic movement.

An Islamic militant Web site said Thursday that Usama bin Laden's deputy would soon release a new message calling for Muslims to support the Islamic militants in Somalia. The Web site did not specify when the message from Ayman al-Zawahiri would be released

"Rush in support of your brothers in Somalia," a banner on the Web site quoted al-Zawahiri as saying.

The Somali Islamic movement denies having any links to Al Qaeda.

Earlier Thursday, Somalia's Interior Minister Hussein Aideed said there are about 3,500 Islamists hiding in the capital and they are "likely to destabilize the security of the city."

Aideed did not explain the source of his information or what prompted his comments. Prime Minister Ali Mohamed Gedi later tried to play down the threat and disputed Aideed's number of Islamists hiding in the capital, although he did not offer his own estimate.

Gedi said his government would begin efforts to disarm Somalis by seizing large arms caches located around Mogadishu. A house-by-house search will follow, the prime minister told journalists, without saying when that will happen.

Thursday was the deadline for people in Mogadishu to surrender their arms. Gedi said the disarmament program was progressing but offered no details. By Wednesday, only a handful of people had heeded Gedi's demand and turned in any weapons in the capital.

In Ethiopia, a top U.S. diplomat said that she hopes African peacekeepers will be in Somalia by the end of the month.

Ugandan President Yoweri Museveni had promised President Bush in a recent phone call that he could supply between 1,000-2,000 troops to protect Somalia's transitional government and train its troops, said Jendayi Frazer, assistant U.S. secretary of state for Africa, after meeting Museveni.

Frazer said there had been no request for U.S. troops or military assistance so far.

Ethiopian Prime Minister Meles Zenawi has pressed the international community to send in peacekeepers quickly, saying his forces cannot play that role and cannot afford to stay long.

Aideed, the Somali interior minister, said that there are about 12,000-15,000 Ethiopian troops in Somalia, and when peacekeepers arrive in the country the Ethiopians will leave. Ethiopia has put the number much lower, at around 4,000, and said it would pull out within weeks.

With the fighting raging just over the Kenya-Somalia frontier, Kenyan Foreign Minister Raphael Tuju said his country had officially closed its border. The U.N.'s humanitarian agency has said there are thousands of Somali refugees reported to be near the border, unable to cross into Kenya.

Tuju said Wednesday that Somali government troops were not threatening civilians so he didn't believe Somalis should be trying to cross the border into Kenya. A Kenyan security helicopter and air force plane were fired at by unidentified gunmen on either side of the border on Wednesday.

Somalia's last effective central government fell in 1991, when clan-based warlords overthrew military dictator Mohamed Siad Barre and then turned on each other. The government was formed two years ago with the help of the United Nations, but has been weakened by internal rifts.