Hundreds of Boko Haram militants and their families have surrendered in Chad in the past month, security and U.N. sources said, in a sign the military campaign against them is making headway.
Boko Haram, which has killed and kidnapped thousands of people, had seized an area approximately the size of Belgium in northeastern Nigeria by last year but has since lost significant ground amid growing regional military pressure.
Analyst and security sources think the militants are probably recent recruits that Boko Haram has struggled to retain as it has ceded territory. Defections of Boko Haram fighters have been reported in Nigeria but are not known to have previously occurred on such a large scale.
"They surrendered to our troops on the front line in Lake Chad," said Colonel Mohammad Dole, Chief Military Public Information Officer for the Multinational Joint Task Force (MNJTF) headquartered in Chad's capital N'Djamena.
"The surrenders are taking place because of the firepower of our operations. The groups, many of them armed, have been arriving since September and their number keeps increasing," he said.
Some 240 militants, most off whom are Chadian, are now being held in detention along with their families, Dole said.
The MNJTF, with troops from Chad, Niger, Nigeria, Cameroon, launched a regional operation in July against the group, which has pledged allegiance to ISIS terrorists.
It has since continued patrols around the waterways of Lake Chad - one of the world's poorest regions whose villages were last year regularly struck by militants, sometimes aboard canoes.
Around 2.6 million people have been displaced in the Lake Chad Basin where Chad, Niger, Nigeria and Cameroon meet.
Signs that regional armies are wresting back control of the Chadian part of the lake is significant since it had been a recruitment hub, even if the group never sought to conquer territory there, said Ryan Cummings, director of consultancy Signal Risk.
"Their presence in Chad was more for recruitment and for resources. Its strikes in the country were punitive," he said, referring to revenge attacks on regional military heavyweight Chad, which has supplied 3,000 troops for the MNJTF.
