Story highlights Eight people were killed in the suicide bombing, officials say

The Somali interior minister was not with the delegation, his office says

The Islamist militia Al-Shabaab claims responsibility for the attack

The radical group has staged several other recent attacks in the nation

A suicide bomber drove a car packed with explosives into a convoy carrying a Qatari delegation in Mogadishu Sunday, killing at least eight people and wounding seven, authorities and witnesses said.

Farah Hassan, who witnessed the aftermath of the attack, said those killed were all bystanders at the busy intersection in Somalia's capital.

Earlier reports about the attack said Somalia's interior minister was traveling in the convoy, but the minister's office said he was not there.

Somali prime minister spokesman Ahmed Adan and District Commissioner Abdi Warsame said no one in the convoy was hurt in the attack.

The radical Islamist group Al-Shabaab claimed responsibility for the bombing, and said six soldiers were killed and nine wounded.

"The mujahideen have today carried out a martyrdom operation in Mogadishu, targeting Somali interior minister convoy," the militant group posted on a pro-Al-Shabaab website.

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Several principal roads in and around the capital were locked down by government troops in recent days amid threats by Al-Shabaab to launch deadly attacks. The site of Sunday's suicide bombing was just reopened a day ago.

Emergency vehicles, sirens wailing, rushed to the gruesome scene, where incinerated bodies and body parts were strewn across the road. The wounded, some of them seriously injured, were rushed to the hospital.

A bulldozer sifted through the rubble, which covered most of the street.

"What have they done to us?" one woman wailed.

The latest attack comes two days ahead of a conference on Somalia in London, where Somali President Hassan Sheikh Mohamud is expected to present his plans to rebuild the military and the country as a whole, as well as solicit international support.

Al-Shabaab has waged several recent attacks in Somalia.

Last month, at least 10 heavily armed militants forced their way into a court building in Mogadishu, killing 29 people, sources said.

In that attack, some assailants detonated explosives while others exchanged fire with government security officers, witnesses said.

At least nine members of Al-Shabaab were also killed, the sources said.

Somalia's president has called the uptick in strikes "nothing but a sign of desperation by the terrorists," saying the militants "are in complete decline."

Somalia's government, backed by African Union peacekeepers, has been battling Islamist guerrillas for years.