Nearly a million children have been forced out of school by the recent earthquake in Nepal and would not be able to return unless immediate action is taken to provide temporary learning spaces, Unicef said in a statement released Thursday. In several districts that faced the worst effects of the April 25 earthquake, more than 90 percent of the schools are believed to have been destroyed.

“Children affected by the earthquake need urgent life-saving assistance like clean water and shelter, but schools in emergencies -- even in a temporary setup -- play a vital role too,” Tomoo Hozumi, Unicef’s representative in Nepal, said. “They minimize disruption to children’s education, protect them from exploitation and abuse, and provide them with messages to keep them safe and healthy. Going to school also allows children to regain a vital sense of routine that can help them come to terms with their experiences.”

In the capital city of Kathmandu, meanwhile, nine out of ten surviving school buildings are currently being used as emergency shelters. They are due to reopen on May 15.

Even before the devastation wreaked by the earthquake, access to primary education had been a major issue in the impoverished nation. However, recent statistics had indicated a major progress toward enrolment of children, which increased from 64 percent in 1990 to more than 95 percent this year. This progress, Unicef warned, is now at risk.

“Unicef’s experience shows that children who are out of school for extended periods, including during emergencies, become less and less likely to ever return to the classroom,” the U.N. agency said in the statement. Moreover, prolonged interruption in education could also cause significant damage to “children’s development and future prospects,” Hozumi said.

So far, over 8,400 people are believed to have died as a result of the 7.8-magnitude earthquake. Over 17,000 people have also been injured. Earlier, the U.N. launched a $415 million emergency appeal to provide vital relief to people affected by the quake.