Around 20 children were injured Thursday when mortar fire hit a primary school in the northern fringes of Myanmar's Rakhine state, an area where the military is locked in battle with Arakan Army (AA) rebels.
The attack happened in Buthidaung township, one of several areas in lockdown, and it is not clear who was responsible.
Scores of civilians have been killed, hundreds injured and some 100,000 displaced since January last year when both sides stepped up operations.
The AA claims to be fighting for more autonomy for ethnic Rakhine Buddhists.
Teacher Thar Aye Maung from Khamwe village told AFP by phone how his school was hit Thursday morning, injuring 21 pupils.
"One girl is badly hurt. Most of the others have injuries to their hands and legs."
"We thought the shells couldn't reach our school."
"(The AA) fires at villages with our shells and then misleadingly claims the military is responsible."
"(They) disproportionately affect civilians in conflict areas, hampering humanitarian aid operations, livelihoods, and the work of human rights monitors."