Power struggles between Somalia's president and prime minister are risking the war-torn country's fragile gains, European Union and United Nations envoys warned Monday in a call for "responsible political leadership."

EU special envoy Alexander Rondos said there was "deep concern" at the "public differences" between President Hassan Sheikh Mohamud and his prime minister, Abdiweli Sheikh Ahmed.

The Kenyan army said it had repelled a machete attack on a military barracks in a tourist resort near Mombasa on Sunday, killing six assailants.

About a dozen youths tried to break into the barracks in the Indian Ocean town of Nyali at around 5:30 am (02:30 GMT), the army said in a statement.

At least one person was killed and two others wounded on Saturday in a car bombing in Somalia's capital Mogadishu, police said.

"One person... was killed and two others wounded this morning after a bomb attached to the car was remotely detonated," said Mohamed Dahir, a police commander in the Hodon district where the explosion happened.

The United States on Thursday issued a stark travel warning for Burundi after threats by al-Shebab militants and imposed a de facto night-time curfew on U.S. government staff in the country.

The State Department warned all American citizens to avoid non-essential travel to the small, impoverished country, nestled in Africa's Great Lakes region.

The African Union has hit back against claims its internationally-funded troops in Somalia have gang raped women and girls, accusing the rights group behind the report of being unfair and inaccurate.

In a letter of response to Human Rights Watch released by the AU on Thursday, the pan-African bloc also said the rights group had undermined peace efforts in war-torn Somalia.

Seven Indian sailors kidnapped by Somali pirates more than four years were freed on Thursday, officials said.

The sailors were released in Harardhere, a coastal town north of Mogadishu, and were flown to the capital.

U.N. chief Ban Ki-moon warned Wednesday that Somalia risks returning to famine without urgent aid, as he visited the war-torn country three years since more than 250,000 people died of hunger.

Ban, along with World Bank chief Jim Yong Kim, met Somali President Hassan Sheikh Mohamud inside the fortified airport zone in Mogadishu, guarded by troops from the 22,000-strong U.N.-backed African Union force.

At least one person was killed and several others wounded on Saturday in a car bombing outside a hotel in Somalia's capital Mogadishu, officials said.

A Somali police official, General Mohamed Yusuf Madale, told reporters the car bomb went off outside the Golden Hotel shortly after midday, "killing at least one person and injuring another one."

Despite reservations from Russia and Jordan, the U.N. Security Council on Friday authorized snap inspections off Somalia's coast of ships suspected of carrying charcoal sold by Shebab Islamists.

About a third of some $250 million in annual revenue from the charcoal trade flows directly to the coffers of the al-Qaida-linked Shebab fighting the Mogadishu government, according to a U.N. monitoring group.

Two Somali journalists from a major radio station have been released on bail after two months in jail but two others remain behind bars accused of inciting violence, colleagues said Wednesday.

Radio Shabelle owner Abdimalik Yusuf Mohamud was released on bail Tuesday, but was ordered to surrender his British passport and remain in Somalia until the court decides if the case will proceed to trial, the National Union of Somali Journalists said.