Insurgents dragged the corpses of two soldiers through the streets of the Somali capital and set the bodies on fire Wednesday after a fierce street battle killed at least seven people, witnesses and medical officials said.

An Associated Press photographer saw insurgents drag the bodies of one Ethiopian soldier and one Somali government soldier through the streets of northeastern Mogadishu and then set them on fire.

As one of the bodies was still burning, women wearing head scarves and long, loose dresses picked up stones and pounded it as a handful of young men looked on.

Ethiopia sent soldiers into Somalia in December to help defeat an Islamic movement that threatened to destroy Somalia's internationally recognized government. While the Islamic forces no longer hold territory, they have started an insurgency to overthrow the government and drive out the Ethiopian troops.

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Somali and Ethiopian troops, supported by tanks and armored vehicles, entered an insurgent stronghold in central Mogadishu before dawn and were met by hundreds of masked insurgents.

"Ethiopian tanks rolled out of the former Defense Ministry and moved into the nearby Shirkole area, which is seen as the stronghold of the insurgent groups, and they met with stiff resistance," said Ali Haji Jama, a resident of the northeastern neighborhood at the center of the fighting.

Other witnesses said minibuses filled with insurgents were racing through the city to reach Shirkole and defend against the Ethiopian advance. The same minibuses were used to carry away casualties, said Muqtar Abdulahi Dahir, a Mogadishu businessman who witnessed the fighting.

Medical officials at Mogadishu's three hospitals said they had recorded at least seven dead and 10 wounded by midmorning.

Somalia's government began the operation at about midnight Tuesday at the former Defense Ministry headquarters and plans to move forces into other parts of the capital, said Mohamed Ali Nur, the country's ambassador in neighboring Kenya.

The operation is meant to try to stop militants from firing rockets at government installations, he told the AP.

Nur denied that any Ethiopian troops were involved in the operation.

Insurgents have fired mortars and rocket-propelled grenades at the Somali forces and their Ethiopian allies almost daily.

Somali leaders have said in recent weeks that they were preparing a major offensive to stop the growing insurgency.

Somalia has been without an effective central government since 1991. The present government has so far failed to assert itself, and the African Union has deployed a small peacekeeping force to defend it. Daily violence has continued in the capital.

Dozens of residents in Mogadishu fled Tuesday after a night of mortar attacks, while another threat — disease — took its toll in the south. Doctors reported that as many as 22 people died in southern Somalia from a suspected cholera outbreak.

A group calling itself the Brigades of Tawhid and Jihad in the Land of Somalia claimed responsibility on Tuesday for the mortar attacks. It said in a statement posted on the Web site of Somalia's routed Islamic movement that it attacked several parts of the capital where "infidels live."

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