"Around 800,000 children have been forced to flee their homes as a result of the conflict in northeast Nigeria between Boko Haram, military forces and civilian self-defense groups," UNICEF said Monday.
The "number of children running for their lives within Nigeria, or crossing over the border to Chad, Niger and Cameroon, has more than doubled in just less than a year."
UNICEF released a report on the crisis titled "Missing Childhoods.
It also launched a social media campaign using the hashtag #bringbackourchildhood. The campaign has "leading Snapchat artists" sharing images based on drawings from children in Nigeria, Chad, Niger and Cameroon. Artwork can also be seen on Facebook, Twitter, Instagram and Tumblr
More than 1.5 million people have fled their homes due to the violence, UNICEF said. About 1.2 million are displaced internally, while others have crossed into Cameroon, Chad and Niger.
"The vast majority of the displaced -- more than 880,000 -- are staying with host communities with little access to humanitarian support, putting additional strains on already stretched health, education and social services," it said.
The April 14, 2014, kidnappings at a girls school in Chibok
by the Islamist group Boko Haram "is only one of endless tragedies being replicated on an epic scale across Nigeria and the region," said Manuel Fontaine, UNICEF regional director for West and Central Africa.
"Scores of girls and boys have gone missing in Nigeria -- abducted, recruited by armed groups, attacked, used as weapons, or forced to flee violence. They have the right to get their childhoods back."
Kids are being used by Boko Haram as combatants, cooks, and lookouts, UNICEF said. "Young women and girls are being subjected to forced marriage, forced labor and rape," it said. At least 196 teachers and 314 schoolchildren were killed in 2014, and more than 300 schools were damaged or destroyed.