Troops from Chad join in the battle against the terror group after it kidnapped 80 people including 50 children from Cameroon.Read the full story ›
Around 30 of up to 80 hostages taken by Boko Haram have been released, Cameroon military said.
Some are said to have escaped while others were freed during a gun fight between the militant group and soldiers.
Military spokesman Colonel Didier Badjeck revealed some of the militants used hostages as human shields.
He did not know how many people were killed and it is not clear how many of those freed were children, following reports up to 50 had been captured.
Suspected Boko Haram fighters torched around 80 homes as they kidnapped dozens of people - including around 50 children - in raids on villages in northern Cameroon, an official has said.
"There was a Boko Haram attack on several localities in the Far North region," Cameroon government spokesman Issa Tchiroma said. "The assailants burnt down about 80 homes and kidnapped several inhabitants including women and very young children."
The latest attack occurred days after Amnesty International released satellite images showing the devastation caused by Boko Haram in two Nigerian towns.
The Islamist militant group has stepped up attacks in the region as Nigeria prepares for a February 14 presidential election.
The early morning kidnapping of 80 people - including around 50 girls and boys - in northern Cameroon is among the largest abductions in the country since Boko Haram fighters ventured over the border from Nigeria last year.
A senior army officer said soldiers intervened and exchanged fire with the fighters for around two hours but could not rescue those taken.
The latest raids on Mabass and several other villages along the border came as neighbouring Chad deployed troops to support Cameroon's forces in the area.
Suspected Boko Haram fighters have kidnapped around 80 people, including some 50 children, in Cameroon, officials said.
A senior army officer said fighters from Nigeria launched the cross-border attack on the northern village of Mabass.
He said the children were aged between 10 and 15 and added that the adults were mainly herders.
A Cameroon government spokesman said three people had been killed in the attack but could not confirm the number taken.
Suspected members of Nigerian militant group Boko Haram have attacked a town in northern Cameroon, killing three people and seizing the wife of the country's vice prime minister.
Military commander Felix Nji Formekong said: "The situation is very critical here now, and as I am talking to you the Boko Haram elements are still in Kolofata town in a clash with our soldiers."
Mr Formekong said vice prime minister Ahmadou Ali was escorted away from the town of Kolofata to the the nearby town of Mora.
Fifa has refused to comment on allegations that Cameroon players were involved in match-fixing in their World Cup games.
Sepp Blatter, the Fifa president, said he was aware of the issue, telling reporters in Rio: "Yes I have been told about this but let them do their work on this investigation."
Fifa spokeswoman Delia Fischer refused to comment on whether the governing body was investigating the claims.
"As we have said consistently - prior to the Fifa World Cup and now during it - we do not provide any comments as to whether or not an investigation is underway with regard to any alleged manipulation in any match, amongst others so as not to compromise any possible investigations," she said.
Cameroon lost all three Group A matches, including a 4-0 defeat by Croatia.
Cameroon's football authorities have confirmed they are looking into claims of "fraud" surrounding the national team's games at the World Cup.
"Recent allegations of fraud around Cameroon's three 2014 World Cup games, especially Cameroon v Croatia, as well the existence of "seven bad apples (in our national team)" do not reflect the values and principles promoted by our administration," FECAFOOT said in a statement.
“We are strongly committed to employ all means necessary to resolve this disruptive matter with the shortest delay,” FECAFOOT's interim president Joseph Owona said.
The allegations stem from reports in German magazine Der Spiegel that a convicted fraudster had accurately predicted Croatia would win 4-0 and that a player would be sent off.
Cameroon's Football Association says it will investigate claims of match-fixing in some of the national team's World Cup games.
French President Francois Hollande has confirmed that seven French nationals - four adults and three children - have been kidnapped in Cameroon by a militant organisation known to French authorities.
Hollande said during a visit to Greece that the group, members of the same family who were apparently tourists, had been seized by a Nigerian-based "terrorist group".