The Cameroonian army said five of its soldiers were killed in clashes with Boko Haram in the country’s far north on Monday, which also left 86 of the Islamist militants dead.

The “series of clashes” took place in the Waza region near the border with Nigeria, said Colonel Didier Badjeck, a spokesman for the Cameroonian defence ministry.

The Cameroonian army had recovered one armoured vehicle from Boko Haram and damaged another, he added.

The troops who were killed belonged to Cameroon’s elite Rapid Intervention Battalion (BIR), which is on the front line in the fight against the Nigeria-based Boko Haram group.

A Cameroonian soldier, speaking on condition of anonymity, said “an ambush by Boko Haram” led to nearly three hours of gun battles.

More than 2,000 Cameroonian soldiers have been deployed in Cameroon’s Far North region since August last year.

Meanwhile, an army official announced on Monday that more than 1,000 people suspected of being affiliated with Boko Haram were being held in the town of Maroua, also in the country’s Far North region.

“At the moment, the prison of Maroua is holding more than 1,000 Boko Haram (suspects),” said Colonel Joseph Nouma, commander of a local operation to combat the Islamist militants.

Boko Haram has grown in power in the area, where Cameroon and Nigeria are linked by a bridge. Militants have carried out repeated massacres of civilians and attacks on villages there, but are now increasingly active against military targets.

Cameroon has joined a military alliance with Chad, Niger and Nigeria to combat Boko Haram, which has stepped up its cross-border attacks in response.