More than 1,300 schools have been totally destroyed in government-held areas of Ukraine since Russia’s 2022 invasion and others have been badly damaged, the U.N. children’s fund UNICEF said on Tuesday.

Persistent attacks mean that only about a third of school-age children there are attending classes fully in person and many are forgetting what they have already learned, it said.

Beyond Ukraine, more than half of the children whose families have fled the conflict to seven countries are not enrolled in national education, UNICEF said, citing language barriers and overstretched education systems.