A suicide bomber killed at least 30 soldiers and wounded several others inside a military academy in Somalia's capital Mogadishu on Monday, a soldier who saw the bodies said.

“We have confirmed 30 dead and 73 others injured from the blast at the military training camp,” an army officer told Reuters news agency on Monday.

The al-Shabaab militant group has claimed responsibility for the early morning attack at Jaalle Siyaad Military Academy.

A military campaign launched by government forces and allied militiamen last year has forced the al Qaeda-linked group from large swathes of territory in southern Somalia, but the militants have continued to stage deadly raids.

Stepped up attacks

In recent weeks, with the military campaign against them stalled as the army prepares a second phase of the offensive, al-Shabaab fighters have stepped up their attacks.

In late May, they killed at least 54 Ugandan peacekeepers at a base south of Mogadishu. For nearly two weeks, they laid siege to Baidoa, one of the country's largest cities. And they have staged a series of raids in Mogadishu this month.

The soldiers killed in Monday's attack hailed from the Lower Shabelle region and had come to the capital for training, said Captain Ali Farah, who knew some of them. He said he was aware of 10 deaths so far.

"The soldiers were being counted in the queue when the suicide bomber blew himself up," Farah said.

Casualty figures

Al-Shabaab said in a statement the bomber had killed 73 soldiers and wounded 124 others. The group typically gives casualty figures that are significantly higher than those provided by the authorities.

Al-Shabaab has been fighting since 2006 to topple Somalia's central government and establish its own rule based on its strict interpretation of Islamic Sharia law.