Suspected militants kidnapped 50 people, mostly women, in northeastern Nigeria this week in the latest mass abduction by fighters who have waged an insurgency for more than a decade, Reuters reported on Wednesday quoting local officials. Boko Haram and Islamic State West Africa Province (ISWAP) fighters have mainly operated in Borno state in the northeast, targeting security forces and civilians, in the process killing and displacing tens of thousands of people. The latest incident took place on Monday in the remote Gamboru area, which shares a border with Chad and Cameroon, said an official of the Civilian Joint Task Force, which helps the army to fight the jihadists. The official, who declined to be named because he was not authorized to speak to the media, said the group of at least 50 people from a camp for internally displaced persons, went to collect firewood on the shores of Lake Chad, where ISWAP is known to operate. They were ambushed by gunmen and made to walk across bushy paths into neighboring Chad, the official said, adding that three of the kidnapped women managed to escape. The Nigerian Army did not respond to a request for comment. Falmata Bukar, one of the three women who escaped, told Reuters by phone that the gunmen had "surrounded us and we were asked to follow them to the bush." She later escaped with two others on Tuesday, she said. Barkindo Saidu, head of Borno's emergency agency, said he was traveling to the area to assess the situation but was not yet ready to declare the people missing. The agency is in charge of camps housing thousands of Nigerians displaced by the insurgency. — CNN