At least 20 children have died after they became trapped in a fire at a school in Niger's capital, Niamey.
The fire started late on Monday afternoon when the children were attending lessons in straw classrooms.
The flames blocked the school gate, so most pupils had to escape over a wall, a teacher's union official quoted by Reuters said.
Most of those who did not manage to escape were attending the school's nursery, officials say.
"Twenty-one classrooms in straw huts caught fire. Around 20 children were trapped in the blaze," fire service commander Sidi Mohamed told public television, AFP reports.
He said firefighters attended the scene in Niamey's Pas Bas district quickly, but "the power of the fire was enormous".
Prime Minister Ouhoumoudou Mahamadou went to the school, on the edge of the capital, to offer his condolences.
Photos shared on social media show crowds gathered by the school looking at the wreckage of the burnt-out scene.
Teachers' union official, Mounkaila Halidou, said there were about 800 students attending the school.
"Those who died were mostly in the preschool," he said.
Niger is the world's poorest nation, according to the UN's development rankings for 189 countries.