ABUJA/MAIDUGURI (Reuters) - When Nigerian Adamu Buba saw a woman in a torn hijab at his friend's wedding last Saturday, he asked two colleagues to serve her food. Moments later, while taking photos of the bride and groom, he heard a loud blast that knocked him to the ground.

The woman in the hijab detonated explosives strapped on her back, killing herself and 10 others. Buba lay bleeding and disoriented.

"All I could see were dead bodies on the ground and body parts all around," said the 34-year-old Buba from a hospital bed in Maiduguri, the capital of Borno state in northeast Nigeria.

The bride and groom survived.

This was the first of four suspected suicide bombings in the past week by women that also targeted a funeral for victims, a hospital and a security checkpoint, which authorities say killed up to 32 people in Gwoza town in Borno, the heartland of an Islamist insurgency.

No group claimed responsibility.

But Gwoza residents blamed Boko Haram and the military said this showed how far the group would go to inflict damage on civilians and security targets.

Residents saw the attacks as punishment for collaborating with security forces against the insurgents. They also said this could be a message to Boko Haram defectors in the town that they were not safe after leaving the group.

"We have always been scared because the presence of ex-fighters in our community is a big threat to our lives," Abubakar Audu, a friend of the groom said from Maiduguri.

Saturday's widely publicised wedding was a perfect target as it drew prominent people, including local politicians.

Boko Haram had last used female suicide bombers in 2020.

Army spokesperson Major General Edward Buba said the attacks were cowardly and meant "to project an image of strength to cover their (Boko Haram) weakness and decline".

Boko Haram has been under pressure from the military and its offshoot Islamic State West Africa Province, with which it is fighting for territory, said Malik Samuel, Nigeria researcher at Abuja-based Institute of Security Studies.

"These issues have severely affected (its) ability to carry out large scale attacks. So, deploying suicide bombers was a devilishly clever way to wreck havoc because it seemed to be a thing of the past," said Samuel.

(Reporting by Ope Adetayo in Abuja and Ijasini Ijani in Maiduguri, Editing by Angus MacSwan)

By Ope Adetayo and Ijasini Ijani