Fierce fighting between heavily armed rival clans in war-torn Somalia has killed at least 26 people in a dispute over grazing land and water, officials said Sunday.

"There are many casualties, the initial reports are of 26 people killed," said Mohamed Abdi Shire, a senior commander of the Ahlu Sunna militia in central Somalia, which controls the region.

Ethiopian troops will remain in Somalia until African Union forces fighting Islamists can take over, Prime Minister Hailemariam Desalegn said Wednesday, as he met with his Somali counterpart.

"We are waiting for AMISOM (African Union Mission in Somalia) force to come and replace us, and until we get that assurance then we will be waiting there," he told reporters.

Somalia's Al-Qaida-linked Shebab fighters briefly took control of a small town on the border with Kenya in a battle that left at least 12 people dead, military officials and witnesses said Sunday.

Heavy fighting broke out late Saturday afternoon in Bulohawo and lasted into the evening, residents and military commanders said, with residents confirming that the Shebab took full control of the town for a few hours before Somali troops were able to reinforce their positions.

Inter-ethnic clashes broke out on Monday in a Nairobi district over a bus bomb blamed on sympathizers of Somalia's Al-Qaida-linked Shebab insurgents, leaving several people wounded.

An AFP reporter at the scene said police used tear gas and fired into the air to contain the violence, which broke out at Eastleigh, a predominantly Somali district of Nairobi where a bomb that went off Sunday on a bus killed seven and wounded many more.

A strong blast rocked Somalia's parliament Wednesday, with at least one person killed, an Agence France Presse reporter at the scene said.

The blast, believed to be a car bomb set off close to the parliament, is the latest in a string of attacks in the war-ravaged Somali capital.

Two suicide bombers attacked a restaurant in Somalia's capital Mogadishu on Saturday, wounding several people, police said, and killing one victim, according to a witness.

"There were two suicide bombers who attacked the Village restaurant. The two of them have died and other people who stayed in the place were injured. We are still investigating the casualties," said Abdi Adan, a Somali police officer.

At least six civilians were killed in war-ravaged Somalia after their bus was hit close to the frontline with al-Qaida-linked Shebab fighters, witnesses said Thursday.

"Six people including two women were killed, and at least five others were seriously injured when a big explosion hit their minibus," said Hassan Yahya, a witness.

Kenyan security forces must end the abuse of residents in crackdowns and reprisal raids in the hunt for suspected backers of Somalia's Al-Qaida-linked Shebab militants, Human Rights Watch warned Thursday.

Since Nairobi invaded southern Somalia last October to attack Shebab bases, a string of attacks have rocked the volatile northeastern region, including grenade blasts targeting both the security forces and civilians.

Somalia's president has appointed as prime minister a relatively little known businessman, Abdi Farah Shirdon Said, senior government sources said Saturday.

"Said has been named as the prime minister," a government official said, speaking on condition of anonymity, ahead of an expected official statement.

Half of Somalia's population wants out of the impoverished, conflict-stricken nation even as it takes the first steps to shed its reputation as the world's most failed state, a new U.N. report says.

The United Nations sent a small army of surveyors across the vast East African nation -- some risking their lives in militant zones now under attack from African Union troops -- to get the views of its long-suffering 9.5 million people for a development survey.