YOLA/ MOGADISHU - At least 27 people were killed and 96 wounded on Friday in two bomb attacks at mosques in Nigeria’s restive northeast, hospital sources said.

A suicide bombing during dawn prayers at a mosque in Maiduguri, capital of Borno state, killed at least 10 people, a hospital source said.

Abdulkadir Ibrahim, spokesman of the National Relief Agency, put the death toll at 27. Another hospital source said 27 people had been wounded. Borno is the birthplace of the Boko Haram insurgency and has been the focus of attacks by suspected members of the militant Islamist group that have killed around 1,000 people since President Muhammadu Buhari took office in May.

A second bomb went off during Friday prayers at a mosque in Yola, capital of Adamawa state, south of Borno, killing at least 27 worshippers, a Red Cross official said. No more details were immediately available. No one has claimed responsibility for the attacks but they bore the hallmarks of the jihadi movement, which has been trying to carve out a state in the northeast of Africa’s most populous country since 2009.

In the meantime, a senior al Shabaab commander and about 20 of his followers have pledged allegiance to Islamic State, the first move of its kind to emerge in the Somali militant group. There was no immediate reaction from al Shabaab’s overall leadership, which aligned itself in 2012 to al Qaeda, a group that has declared Islamic State’s leader illegitimate. Experts have been watching to see if the rise of Islamic State in Syria, Iraq and other battlefields, would draw al Shabaab’s public support, but said the impact of any such alliance would be largely symbolic given geographical distance would hinder an exchange of material supplies.

“We, the mujahideen of Somalia, declare allegiance to the caliph as Ibrahim ibn Awad ibn Ibrahim al-Awad al-Qurashi,” Abdiqadir Mumin, an al Shabaab commander in the Puntland region of Somalia, said in an audio tape published on YouTube. Nigerian militants Boko Haram also pledged allegiance to Islamic State this year, a move seen as highlighting a desire by African jihadists to link up with others in the Middle East and elsewhere.

Islamic State has accepted pledges of allegiance from groups in the Middle East, Afghanistan, Pakistan and North Africa. A follower of al Shabaab’s Mumin confirmed the veracity of the recording declaring allegiance to al-Qurashi, better known as Abu Bakr al-Baghdadi, the leader of Islamic State and self-proclaimed caliph of the Muslim world.

“Senior leader Abdiqadir Mumin and his 20 fighters, including me, joined ISIS,” one of Mumin’s supporters told Reuters by telephone, using one acronym for Islamic State. Mumin had been based in the Galgala hills in Somalia’s semi-autonomous Puntland region, said the supporter, who asked not to be identified. The 20 came from a group of 300 in Galgala, he said, adding that his group had now moved to another area.

“The other fighters rejected us and remained in the Galgala hills,” he said. There are no clear figures for the strength of al Shabaab, but diplomats put it at several thousand fighters. One expert said the announcement suggested a small split in the ranks. Al Shabaab, which ruled much of Somalia for several years until 2011, was driven out of most urban centres by an offensive launched by African Union forces and Somali troops last year. Some were driven north to Puntland, experts say. Puntland’s security minister dismissed Mumin’s declaration. “Puntland forces are ready and determined to eliminate ISIS,” Abdi Hirsi Ali said.