Conflict has forced an estimated 1 million children out of school in north-eastern Nigeria, Cameroon, Chad and Niger, dpa cited the UN as saying. More than 2,000 schools have been closed for more than a year because of conflicts in the four countries, where thousands have been killed and forced to flee their homes due to attacks by terrorist insurgent group Boko Haram, the UN Children's Fund said in a statement on Tuesday. "The conflict has been a huge blow for education in the region, and violence has kept many children out of the classroom for more than a year, putting them at risk of dropping out of school altogether," said Manuel Fontaine, a director for UNICEF in west and central Africa. In far north Cameroon, only one of the 135 schools closed in 2014 has reopened this year, UNICEF said.