A young woman strapped with explosives blew herself up Wednesday at a ceremony in the Somali national theatre attended by the prime minister and other officials, killing at least two.

She detonated her suicide belt as Prime Minister Abdiweli Mohamed Ali was on a podium addressing 200 people gathered to mark the first anniversary of the country's satellite TV network, an Agence France Presse reporter who witnessed the incident said.

Ethiopian soldiers and pro-government Somali forces closed in on a key town in southwest Somalia Thursday, battling al-Qaida allied Shebab insurgents, official and witnesses said.

Heavily armed troops advanced towards the town of Hudur, capital of the Shebab-controlled Bakool region, about 90 kilometers (56 miles) from the Ethiopian border.

British hostage Judith Tebbutt, kidnapped in Kenya over six months ago by gunmen who killed her husband, said Wednesday she was "happy" after she was released in Somalia to be flown to Nairobi.

Tebbutt, 57, was taken on September 11 from a remote Kenyan beach resort near the Somali border by assailants who shot dead her husband David in a late-night raid.

A car bomb exploded in Somalia's war-torn capital Mogadishu on Wednesday, wounding at least one security officer in the latest in a spate of insurgent attacks, officials said.

"Security forces foiled a car bomb attack intended to kill innocent civilians," said Abidweli Said, a police official. "One security officer who had sealed off the road to inspect the car was injured."

Al-Qaida allied Islamist gunmen seized the key town of Dhusamareb in central Somalia Tuesday, as Shebab commanders called on fighters to intensify attacks against government and regional forces.

Witnesses said Shebab fighters on pickup trucks mounted with machine guns stormed the town at dawn, driving out the pro-government militia Ahlu Sunna Wal Jamaa, an Ethiopian-backed force who follow Somalia's traditional Sufi branch of Islam.

Somalia's al-Qaida allied Shebab insurgents fired mortars at the presidential palace in the capital overnight, killing six civilians in a camp for displaced people nearby.

The hardline Islamist group said its salvo of "midnight mortar attacks" were targeted at the palace, and boasted of killing African Union and government soldiers.

A U.S.-born Islamist fighter viewed as a key foreign leader within Somalia's al-Qaida allied Shebab militia has said he fears his life is now in danger from fellow extremists.

Omar Hamami -- better known as Abu Mansoor al-Amriki -- gave the warning in an undated video posted on several Somali websites and YouTube Saturday.

A suicide bomber blew himself up Wednesday at the compound of Somali President Sharif Sheikh Ahmed, killing at least two people, police said.

The bomber detonated an explosive vest at the highly guarded compound, but it was not immediately clear if President Sharif Sheikh Ahmed, who was in Ethiopia on Tuesday, was back in the country.

Kenyan police said Monday they have arrested four people in connection with grenade attacks that killed six people in Nairobi, which Kenya blames on supporters of Somali Shebab insurgents.

"On the Al-Shebab threats and attacks at the Machakos bus terminus, four highly suspected criminals were arrested and are undergoing intensive interrogation," Nairobi Provincial Police chief Antony Kibuchi said.

Kenya faced a new terror threat on Sunday after a grenade attack blamed on Somali Islamist militia killed six people and injured 63 in a bus terminal in the capital Nairobi.

Four grenades were thrown Saturday night only yards apart from a car driving past the busy terminal, Internal Security Minister George Saitoti said Sunday.