Women took to the streets of this strategic port town Tuesday to protest the arrival of a radical Islamic militia, one day after the militants opened fire on a larger protest here and killed a teenager.

Militiamen quickly broke up Tuesday's protest and arrested 20 women, according to relatives of the demonstrators who didn't want to be named for fear of reprisals. The militants also parked their "technicals" — trucks mounted with guns — along roads to prevent gatherings.

The group's strict and often severe interpretation of Islam raises memories of Afghanistan's Taliban, and contrasts with the moderate Islam that has dominated Somali culture for centuries. Somalis fleeing the conflict have pushed the number of refugees in neighboring Kenya to the highest level in a decade, the United Nations World Food Program said Tuesday.

The number of registered refugees in Kenya has reached 240,000, with thousands more new arrivals, straining resources severely, the U.N. said in a statement.

The United States has accused the Islamic group of sheltering suspects in the 1998 Al Qaeda bombings of U.S. embassies in Kenya and Tanzania. Al Qaeda chief Usama bin Laden has portrayed Somalia as a battleground in his war on the U.S.

Still, some Somalis have embraced the radicals because they have brought a semblance of order in a troubled corner of Africa.

CountryWatch: Somalia

The country's official government was formed two years ago with the support of the United Nations, but it has failed to establish any control outside its base in Baidoa, 150 miles from the capital, Mogadishu.

The militia has been sweeping through southern Somalia since taking over the capital in June. On Sunday, the militia took Kismayo, 260 miles southwest of Mogadishu, without a fight, although thousands protested their presence the following day.

Islamic militiamen wearing white headbands opened fire on the crowd, killing a 13-year-old boy, said resident Abdiqadir Filibin. Two other children were injured, witnesses said on condition of anonymity for fear of reprisals. Sporadic gunfire could also be heard.

"There are Islamic technicals everywhere in the city," said Abdirahman Abdullahi Farah. "We tell them to go back to Mogadishu or face ejection by force."

North of Kismayo, troops from neighboring Ethiopian arrived Monday to support the weak government. Witnesses saw about 300 Ethiopians in a convoy of 50 armored trucks in Bardaale, 40 miles west of Baidoa, the only town held by the government.

Islamic forces believe Ethiopian troops aim to cut off their route between Kismayo and Mogadishu, and called their incursion a declaration of war.

Several thousand demonstrators protested against the Islamic militia Monday in Kismayo. Militiamen with white bands on their heads opened fire on the protesters. Kismayo resident Abdiqadir Filibin said he saw a 13-year-old killed.

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Somalia has not had an effective national government since 1991, when warlords overthrew dictator Mohamed Siad Barre and then turned on one another, throwing the country into anarchy.

Hassan Turki, a leader of the Islamic militia, acknowledged Monday for the first time that foreign fighters were helping the militants. He was speaking to a demonstration in support of his group in Kismayo. Turki, who is rarely seen in public, is on the U.S. and U.N. lists of suspected terrorists for having alleged ties to Al Qaeda.

In an interview with the AP on Monday, Somali Prime Minister Ali Mohamed Gedi said "terrorists" dominate the Islamic group. Speaking in neighboring Kenya, he called on the U.N. to partially lift an arms embargo to allow for the deployment of African peacekeepers.

The Islamic group opposes any foreign intervention in the country.

The Islamic group and Gedi's government have agreed to a cease-fire, but the Islamic fighters have continued to advance across the country.