BAIDOA, Somalia (Reuters) - Ethiopian Prime Minister Meles Zenawi said on Sunday he was waging war against Somalia's Islamists to protect his country's sovereignty, intensifying a conflict that threatens to engulf the Horn of Africa.
It was Ethiopia's first public admission of military involvement in Somalia, where for the first time it sent warplanes on Sunday to pound the Islamist fighters now encircling the weak interim government.
Ethiopian officials have said the Somalia Islamic Courts Council (SICC), which now controls most of Somalia except for the government-held town of Baidoa, is a terrorist group backed by Ethiopia's enemy, Eritrea.
"Ethiopian defense forces were forced to enter into war to the protect the sovereignty of the nation and to blunt repeated attacks by Islamic courts terrorists and anti-Ethiopian elements they are supporting," Meles said in a televised address.
"Our defense forces will leave as soon as they end their mission."
Despite the military campaign, Meles said Ethiopia supported talks between the two sides to set up a joint administration.
Earlier, Ethiopian Information Minister Berhan Hailu said the operation had targeted several sections of the battle front including Dinsoor, Bandiradley and Baladwayne and the town of Buur Hakaba, close to Baidoa. Fighting on the front has now raged for six days.
Somalia's ambassador to Ethiopia, Abdikarin Farah, said government forces had killed 500 Islamist troops, most of them Eritreans, in two days of heavy fighting, but there was no independent confirmation of the death toll.
The Islamists, armed with machine-guns and mortars, say they have killed hundreds of pro-government troops, but aid agencies put the total number of dead at dozens.
The Islamists claim broad popular support and say their main aim is to restore order to Somalia after years of warlord rule and anarchy.
They said Ethiopia, which has also sent tanks toward the front in the last few days, had used MiG fighters and helicopters against their forces. Somali witnesses reported that the aircraft had been firing missiles.
Ethiopia's Farah said the Islamists had killed 10 government soldiers and wounded 13. He said the government had taken 280 prisoners, including Pakistanis, Afghans and Sudanese.
Diplomats fear the war will not only suck in Ethiopia and Eritrea but also attract foreign jihadists answering the Islamists' call for a holy war against Christian-led Ethiopia.
Ali Dahir Horow, a resident of Baladwayne, 190 miles (300 km) north of Mogadishu, said one airstrike had killed two people.
"People started fleeing once the planes fired at the town," he said, adding that most of the missiles nearby hit Ceel Jaale, which many people escaped to after last month's heavy flooding.
DISASTER FOR FLODD VICTIMS
U.N. aid agencies said the conflict would have disastrous consequences for efforts to supply food and aid to 1.4 million people suffering from the floods.
The European Union condemned the bombardments and exchanges of artillery fire, and urged both sides to return to talks.
But the war against old foe Ethiopia has roused the support of many Somalis.
In the Islamist-controlled port city of Kismayu, women and children waved goodbye to 1,000 men who had volunteered for the frontline. Dressed in ragged fatigues, the men sped off in camouflage trucks to the chants of "Victory is ours."
Further north in Mogadishu, women and children gathered in a market to badger men walking along the streets to join the war.
"They told me to wear their clothes if I will not go to war," said Abdi Rashid. "They said I'm not a man, because all men are on the frontline, so I should wear women's clothes."
The SICC captured Mogadishu and a swathe of south Somalia in June, frustrating the Western-backed government's aim of restoring central rule for the first time in 15 years.
Somalia analyst Matt Bryden said he did not expect either side to win the war decisively.
"The Ethiopians are trying to hit the Islamists hard enough that they will come to the negotiation table," he told Reuters. "But they run the risk that the war will become a protracted and unwinnable conflict."
Military experts estimate Ethiopia has 15,000-20,000 troops in Somalia, while Eritrea has about 2,000 behind the Islamists.
Eritrea denies it has sent troops.