The US ambassador to the United Nations condemned the attack.
Pictures obtained by The Associated Press on Friday showed that two stone school buildings were demolished in the attack. No one was hurt or killed despite the fact school was in session.
Susan Rice, the US ambassador to the UN, said she was outraged by what she called a “heinous” bombing.
The Nuba Mountains have been an area of conflict between Sudan’s military and a rebel group formerly aligned with South Sudan for months.
Tens of thousands of people have fled the violence. Rice said the conflict is affecting more than 500 000 people.- AP