Neighbours rushed to school to help put out blazepublished at 09:35 British Summer Time 6 September
The fire started around midnight in a dorm housing 156 boys, BBC Africa correspondent Anne Soy says.
Speaking on BBC News this morning, she says after seeing the fire, "neighbours rushed to the school" to help put it out.
It is still a matter of piecing together information but parents have gone to the school to look for their children.
Most people would have found out about the fire from the media, she says.
And on how it started, Soy adds that there are no theories yet. Some witnesses have said by the time they woke up, their dormitory was "engulfed".