Boko Haram fighters have shot or burned to death about 90 civilians and wounded 500 in ongoing fighting in a Cameroonian border town near Nigeria, officials in Cameroon said Thursday.

Some 800 Islamic extremists attacking the town of Fotokol have "burned churches, mosques and villages and slaughtered youth who resisted joining them to fight Cameroonian forces," Information Minister Issa Tchiroma Bakari said.

The insurgents from Nigeria also looted livestock and food in the fighting that began Wednesday and continued on Thursday, Bakari told The Associated Press.

Boko Haram is using civilians as shields, making it difficult to confront them although reinforcements have arrived in Fotokol, according to military spokesman Col. Didier Badjeck.

Schools also have been razed by the insurgents, whose nickname, Boko Haram, means "Western education is forbidden" in the Hausa language.

Hundreds of insurgents were killed Wednesday compared to the loss of 13 Chadian and 6 Cameroonian troops, Defense Minister Edgard Alain Mebe Ngo said. At least 91 civilians have been killed and most of more than 500 wounded people cannot be immediately taken to the hospitals, he said. There was no way to immediately confirm the account independently.

The fighters are believed to have crossed into Cameroon from nearby Gamboru, a Nigerian border town that had been an extremist stronghold since November.

Gamboru was retaken earlier this week and the fighters driven out by Chadian and Nigerian air strikes supported by Chadian ground troops.

African Union officials on Thursday were finalizing plans for a multinational force to fight the spreading Boko Haram attack, although there are questions about funding.

The AU last week authorized a 7,500-strong force from Nigeria and its four neighbors, Cameroon, Chad, Niger and Benin.

Senior officers from the U.N. peacekeeping department are attending the meeting in Yaounde, Cameroon's capital, said a U.N. official.

The Africans want U.N. Security Council approval and money to fund the mission, said the official who spoke Wednesday at the United Nations and insisted on anonymity because he was not authorized to speak to the press on the meeting.

France's President Francois Hollande said Thursday his country is providing support with weapons, logistics and operations for the multinational effort.

At a news conference in Paris, he stopped short of saying whether France is actually involved in military action itself. France has a big air base at N'Djamena, the capital of Chad, which will lead the multinational force.

International concern has grown as Boko Haram has increased the tempo and ferocity of its attacks just as Nigeria is preparing for presidential and legislative elections on February 14.

Some 10,000 people were killed in Boko Haram violence last year compared to 2,000 in the first four years of Nigeria's Islamic uprising, according to the Council on Foreign Relations.