Boko Haram Islamic extremists struck the northeast Nigerian city of Maiduguri for the first time in months Sunday with rocket-propelled grenades and multiple suicide bombers, witnesses said. At least 15 people were killed but the toll was feared many times higher.

They said the suicide bombers blew themselves up as soldiers were trying to repel an attack by insurgents who arrived firing from the back of three trucks and launched grenades that set homes on fire in Duwari village, near a major military barracks.

"We just came out of the mosque after evening prayers, then we started hearing gunshots… then suddenly there was the sound of a blast," said Nene Hassan, a village resident.

Militants appear to have fired indiscriminately from the back of three trucks attacked the outlying village of Dawari. As people were fleeing, a woman ran into a suburb yelling "Boko Haram, Boko Haram."

When people gathered, she detonated herself, according to village head Bulama Isa.

A second woman exploded in the midst of a family.

Other witnesses to Sunday's attack described a chaotic scene.

"More body parts are just lying everywhere," said Mustapha Ahmadu. Alhaji Jiddari, another resident, said the village was set on fire during the shootout between the army and the attackers. 

Focus on soft targets

The insurgency in Nigeria has killed thousands and displaced more than two million people in the remote northeast.

Sunday's attack comes as Nigeria's government says it has contained the Islamic uprising that has killed 20,000 people in six years.

Maiduguri, the city under attack, is the birthplace of Boko Haram, which emerged as a much more radical entity after Nigerian security forces attacked their compound there, killing 700 people in 2009.

Since losing most of the territory the group seized earlier this year to the army, Boko Haram has resorted to hitting soft targets such as markets, bus stations and places of worship, as well as hit-and-run attacks on villages, mainly in Borno state.

Other bombers intercepted

Nigerian troops "intercepted and destroyed" 10 suicide bombers, according to PR Nigeria, an agency that disseminates government news.

"The troops laid ambush on the terrorists' suspected routes. ...The suicide bombers were intercepted in three different locations approaching the city," PR Nigeria said, quoting the military.

The area that was attacked is close to Giwa Barracks, a major military base attacked several times in the past by the extremists. In January 2014, Boko Haram attacked the base and freed hundreds of detainees.

With files from Reuters