Villagers have reported some civilian casualties in near-daily bombardments in north-eastern Nigeria in the past

Cameroon soldiers stand guard at a lookout post as they take part in operations against Boko Haram near Nigeria's Borno state, where a refugee camp was mistakenly bombed (AP/Edwin Kindzeka Moki)

A Nigerian air force fighter jet on a mission against Boko Haram extremists has mistakenly bombed a refugee camp, killing more than 100 refugees and aid workers, a Borno state official said.

The state government official was helping to coordinate the evacuation of the wounded from the remote area by helicopters.

Military commander Maj Gen Lucky Irabor confirmed the accidental bombardment in north-east Rann, near the border with Cameroon, saying "some" civilians were killed.

It is believed to be the first time Nigeria's military has admitted to making such a mistake.

The International Committee for the Red Cross said six staff members and volunteers with the Nigerian Red Cross were among the dead and 13 were wounded.

"They were part of a team that had brought in desperately needed food for over 25,000 displaced persons," spokesman Jason Straziuso said in a statement from Nairobi, Kenya.

Two soldiers were also wounded as well as Nigerians working for Doctors Without Borders, Maj Gen Irabor said, without giving a precise figure.

Doctors Without Borders said its team based in Rann had counted 50 bodies and treated 120 wounded.

A statement from spokesman Etienne l'Hermitte in Geneva urged authorities to facilitate cross-border land and air evacuations.

"Our medical and surgical teams in Cameroon and Chad are ready to treat wounded patients. We are in close contact with our teams, who are in shock following the event," the statement said.

Maj Gen Irabor said he ordered the mission based on information that Boko Haram insurgents were gathering in the area, along with geographic coordinates. It was too early to say if a tactical error was made, he said.

The general, who is the theatre commander for counter-insurgency operations in north-east Nigeria, said the air force would not deliberately target civilians but there will be an investigation.

Villagers in the past have reported some civilian casualties in near-daily bombardments in north-eastern Nigeria.

Some of the schoolgirls kidnapped by Boko Haram in 2014 and freed last year have said three of their classmates were killed by air force bombardments, according to the freed girls' parents. Of the nearly 300 schoolgirls who were abducted, 196 remain missing.

The bombings have helped drive Boko Haram out of many towns and villages and, according to Nigeria's president, Muhammadu Buhari, the insurgents' last stronghold in the Sambisa Forest last month.

Boko Haram's seven-year Islamic uprising has killed more than 20,000 people and forced 2.6 million from their homes, creating the continent's worst humanitarian crisis, with the United Nations warning some 5.1 million people face starvation.

AP

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