Violence by militant group Boko Haram in and around north-east Nigeria has forced more than a million children to drop out of school, the United Nations said on Tuesday. More than 2,000 schools in Nigeria, Cameroon, Chad and Niger are closed because of conflict in the region. Hundreds of others have been looted or destroyed, the UN’s children’s agency UNICEF said.

Boko Haram, which was originally based in Nigeria, has intensified its operations in neighbouring countries, Thomson Reuters Foundation reported. This is even more troubling as the children who have dropped out of schools there are especially vulnerable to abuse, abduction or even recruitment into the militant group.

"Schools have been targets of attack, so children are scared to go back to the classroom," UNICEF's West and Central Africa regional director Manuel Fontaine said. In 2014, Boko Haram launched an attack on a school in the Nigerian state of Yobe, killing 59 students. Moreover, while some of the schools in the area have been reopened, many of them are overcrowded because they also house people who have been displaced because of the conflict.