Nigerian military has commuted the death sentences handed to 66 soldiers for mutiny over claims they refused to fight Boko Haram Islamists, a spokesman said on Saturday.

Instead, each soldier will serve a 10-year prison term.

Brutal weekend attacks on three villages by Boko Haram Islamists in the restive northeast of Nigeria have left 30 dead and 20 others wounded, a vigilante told AFP.

"Most of the victims were slaughtered and most of the wounded (had suffered) machete cuts," Mustapha Karimbe, a civilian helping the Nigerian military fight Boko Haram, said of Saturday's attacks in the villages of Warwara, Mangari and Bura-Shika in Borno state.

Boko Haram gunmen have torched almost an entire village near the northeast Nigerian town of Chibok from where over 200 schoolgirls were kidnapped, a resident who fled and a local elder said Tuesday.

The raid in Takulashi village happened on Sunday and saw the Islamists loot food supplies, two days after fighters stole more than 200 cattle from the same location.

An 11-year-old boy has been arrested as a "potential suicide bomber" at a camp for people displaced by the Boko Haram conflict, according to Nigeria's military.

Army spokesman Colonel Sani Usman said troops detained the youngster at the Dalori camp near the Borno state capital, Maiduguri, on Tuesday.

Boko Haram on Saturday claimed responsibility for a suicide bombing on a Shiite Muslim procession near the northern Nigerian city of Kano that killed 22 people.

The hardline Islamist group said in a statement in Arabic on social media its bomber "detonated his explosives which led to the death" of the victims on Friday.

Nigeria repeatedly claims to have severely weakened Boko Haram and is eyeing an end to the conflict by year-end, yet the Islamists still show a capacity to launch deadly attacks.

Most of the nearly 1,500 people killed in Nigeria since President Muhammadu Buhari came to power in May have died in suicide and bomb attacks on northeastern towns and cities.

Zainabu Ali cradles her infant son Ibrahim in her arms as he sleeps in a three-bedroom house that she shares with about 20 family members in the north Nigerian city of Kaduna.

The family fled Izghe in Borno state in February 2014, when Boko Haram fighters dressed in military uniform stormed the village and slaughtered 106 people, including an elderly woman.

Senior military, security and intelligence figures in Nigeria on Thursday questioned President Muhammadu Buhari's December deadline for an end to the Boko Haram conflict, calling it "unrealistic".

The Centre for Crisis Communication, a research and advisory body independent of government, said the deadline was "not tenable" given the continued wave of bombings in the northeast.

Nigerian troops were denied weapons to fight Boko Haram and thousands of lives were lost because of rampant fraud in the procurement process, President Muhammadu Buhari has alleged.

Buhari ordered anyone involved in corrupt multi-billion dollar deals for weapons and equipment to be "brought to book" after receiving a report from a committee set up to probe the issue.

Soldiers patrolled the streets and residents surveyed damage to their homes and businesses in eastern Nigeria on Monday, after deadly violence linked to the appointment of the country's first female governor.

At least seven people were killed and 15 injured on Sunday in clashes between supporters of the ousted governor of Taraba state, Darius Ishaku, and Aisha Alhassan in the town of Wukari, according to police.