A Kenyan fighter pilot whose jet crashed in an area controlled by Al-Qaeda-affiliated Shebab fighters in southern Somalia is missing, the army said Friday.

The Shebab said they shot down the warplane on Thursday and "destroyed" the body of the pilot, who was returning from a bombing raid on an extremist base.

A Kenya military plane crashed Thursday in war-torn southern Somalia, the army said, blaming "technical problems", while the Shebab fighters boasted they had shot it down.

Kenyan troops entered southern Somalia three years ago to fight the al-Qaida-affiliated Shebab rebels, later joining an African Union force.

At least 310 people have been killed and over 220,000 fled their homes in attacks in Kenya this year, the United Nations said Thursday, warning of rising conflict.

Cattle rustling and revenge killings between rival communities are common in Kenya's remote and impoverished northern regions, an area awash with automatic weapons.

Somali lawmakers presented a motion in parliament Thursday to oust the prime minister, amid warnings the power struggles and political turmoil could damage efforts to rebuild the war-torn nation.

President Hassan Sheikh Mohamud and his prime minister, Abdiweli Sheikh Ahmed, have been at odds for months, prompting international backers to warn infighting is putting at risk the fragile gains made, with the al-Qaida-affiliated Shebab rebels still carrying out regular attacks.

Somalia's Shebab insurgents said they had assassinated a former lawmaker and his bodyguard and wounded another MP in a drive-by shooting in Mogadishu on Thursday to show the government they remained a threat.

Gunmen in a moving car opened fire as the lawmaker drove through the center of the city, before racing off, witnesses said. MP Mustafa Mayow was wounded in the attack.

Four people were killed and nine wounded in Somalia's capital Mogadishu on Wednesday when a suicide bomber rammed a car packed with explosives into a U.N. convoy, police and rebels said.

The convoy of armored vehicles were ferrying staff between Mogadishu's heavily-fortified airport and a protected U.N. base in the city when it was hit close to the airport gate.

Kenya's interior minister and police chief were removed from their posts on Tuesday, hours after Somalia's Shebab rebels carried out a fresh massacre in the northeast of the country.

In a televised address to the nation, President Uhuru Kenyatta also vowed his security forces will "intensify the war on terrorism" after a spate of killings in the country by the al-Qaida-affiliated insurgents.

Somalia's Shebab rebels on Tuesday said they carried out the massacre of 36 quarry workers in northeast Kenya, and vowed to be "uncompromising, relentless and ruthless" in fighting Kenya.

"In another successful operation carried out by the Mujahideen, nearly 40 Kenyan crusaders met their demise after a unit from the Saleh Nabhan brigade raided them in the midnight hours of Monday at Koromei, on the outskirts of Mandera," Shebab spokesman Sheikh Ali Mohamud Rage said in a statement to Agence France Presse.

A Kenyan policeman was shot dead and another seriously wounded in a new attack by suspected Shebab militants in northeastern Kenya on Saturday, police said.

The shooting, which occurred near the Dadaab refugee camp, came a week after the al-Qaida-affiliated Somali rebels executed 28 civilians in the far northeast.

An engineer working with a Turkish company was killed on Thursday in a bomb attack in Somalia's capital Mogadishu, police said.

There was no immediate claim of responsibility, although Al-Qaida-affiliated Shebab rebels have been blamed for a string of killings targeting politicians, returning diaspora and anyone linked to foreign companies or the internationally-backed government.