MOGADISHU, Somalia - Hundreds of Ethiopian troops arrived to protect Somalia's government Friday as witnesses said a powerful Islamic militia massed nearby, raising concerns of clashes between the two forces.

Somalis walk in floodwaters in the village of Afgoi, Friday, Nov. 24, 2006.  [AP]

More than 130 trucks carried the Ethiopians into Baidoa, the only town controlled by the government, residents said.

"They parked their trucks around the town," Nunay Selah said by telephone. "They are digging trenches."

The standoff is between the transitional federal government, which has UN recognition but little authority on the ground, and the Council of Islamic Courts, which controls most of southern Somalia.

Residents as far away as Bur Hakaba - 40 miles east of Baidoa - were evacuating.

"We are seeing strong military movements from both sides," said Mohamud Ahmed, a father of six. "We don't believe we will be able to continue living in our town peacefully."

Ethiopia, a largely Christian nation, fears the emergence of neighboring Islamic state and has acknowledged sending military advisers to help Somalia's government. But Prime Minister Meles Zenawi has repeatedly denied sending a fighting force.

A confidential UN report obtained last month by the AP said 6,000 to 8,000 Ethiopian troops were near Somalia's border with Ethiopia, backing the interim government. The report also said 2,000 troops from Eritrea are inside Somalia supporting the Islamic movement.

Somalia has been without an effective central government since warlords toppled Mohamed Siad Barre in 1991 and then turned on each other, carving much of the country into armed camps ruled by violence and clan law.

The government was established two years ago with the support of the United Nations to serve as a transitional body to help Somalia emerge from anarchy. But the leadership, which includes some warlords linked to the violence of the past, wields no real power outside Baidoa.

The Islamic council, meanwhile, has been steadily gaining ground since seizing the capital, Mogadishu, in June. The United States has accused the group of sheltering suspects in the 1998 al-Qaida bombings of US embassies in Kenya and Tanzania, which the group denies.

The Islamic movement's strict interpretation of Islam raises memories of Afghanistan's ousted Taliban regime.