( CNN ) The United Nations is appealing for $ 174 million to help Nigerian refugees who 've fled to neighboring nations following militant attacks . Boko Haram has killed thousands in the nation 's northeast by attacking villages , schools , churches and mosques . It has also kidnapped students , including more than 200 schoolgirls abducted in April last year . A majority of them remain missing . The militants have attacked relentlessly for six years , sending 192,000 people seeking shelter in Cameroon , Niger and Chad . `` Displaced people in northeastern Nigeria and across borders are in a very dramatic situation , they fear for their lives and are at this point unable to return to their homes , '' said Liz Ahua , who 's coordinating Nigerian refugee efforts for the U.N. Aid agencies are scrambling to provide the refugees with clean water , shelter , food and access to education . `` In the refugee camps , thousands of school-age refugee children can not attend school because of lack of classrooms and teachers , '' Ahua said . Mental health needs are crucial to help the survivors of physical attacks and those who 've witnessed violence , according to the U.N . Some children are separated from their parents amid the trauma . `` The conflict has had a devastating impact on children , including many who were forcibly recruited by the insurgents in Nigeria , '' Ahua said . The appeal encompasses the needs of 23 agencies and nongovernmental organizations helping the refugees . `` Adequate funding is crucial to make sure aid agencies can improve the living conditions for refugees in asylum countries and respond to their protection needs , '' Ahua said . `` We relocate refugees away from the conflict border areas , and establish additional refugee camps where needed . '' The Islamist group has said its aim is to impose a stricter form of Sharia law across Nigeria , which is split between a majority Muslim north and a mostly Christian south . An additional 1.2 million people are displaced within Nigeria as a result of the insurgency . CNN 's Pierre Meilhan contributed to this report .
Boko Haram has killed thousands in the nation 's northeast since 2009 . Aid agencies are scrambling to provide the refugees with clean water , shelter , food and education .