MOGADISHU, Somalia - Gunmen attacked a Somali police station Sunday, sparking an hourlong battle that killed two people just hours after two other stations were hit with machine-guns and rocket-propelled grenades, witnesses said.

The increased violence in Mogadishu is boosting fears that the Somali government's tenuous grip on power isn't enough to safeguard this notoriously violent city.

"The gunmen ran away after reinforcements arrived to help the police," said Ifah Ahmed Ali, who witnessed the attack Sunday in northern Mogadishu. Late Saturday, gunmen attacked two police stations, wounding five people.

It was not immediately clear whether the victims were civilians.

The Somali government has been putting more soldiers on the streets this week as Ethiopian troops -- whose military strength was crucial to helping drive out a radical Islamic militia last month -- begin pulling out of the country.

Government spokesman Abdirahman Dinari has blamed the spate of recent violence on the Council of Islamic Courts, which has vowed to launch an Iraq-style guerrilla war from their hiding places.

No group has claimed responsibility for the attacks.

The withdrawal of Ethiopia, which says it cannot afford to stay in Somalia, raises a sense of urgency for the arrival of a proposed African peacekeeping force. The African Union has approved a plan to send about 8,000 peacekeepers for a six-month mission that would eventually be taken over by the U.N.

South Africa dashed hopes Friday that it would contribute to a peacekeeping force in Somalia, with Defense Minister Mosiuoa Lekota saying the country's forces already were overstretched. Nigeria, Malawi and Uganda have said they want to contribute troops, but no firm plans are in place.

Also Saturday, 23 people accused of supporting the Islamic courts arrived in Mogadishu after being arrested in Kenya. Dinari said Sunday that the wives of three "terrorists" were among them.

"They were blindfolded and shackled with chains on their feet and handcuffs behind their backs," said Ahmed Yacqub, who saw the prisoners get off a plane at Mogadishu International Airport.

Many Somalis resented the Ethiopian presence; the countries fought a war in 1977. But without Ethiopia's tanks and fighter jets, the Somali government could barely assert control outside one town and could not enter the capital, Mogadishu, which was ruled by the Council of Islamic Courts. The U.S. accused the group of having ties to al-Qaida.

Earlier this month, Ethiopian and U.S. forces were pursuing three top al-Qaida suspects but failed to capture or kill them in an AC-130 strike in the southern part of Somalia.

A main target was Fazul Abdullah Mohammed, one of three senior al-Qaida members blamed for the 1998 bombings of the U.S. embassies in Kenya and Tanzania.