Interior Ministry spokesman Tariq Arian said that over 50 were killed and more than 100 others were injured during three back-to-back explosions on Saturday afternoon in the west of Kabul.
However, sources say that 58 people, mainly school girls, were killed and 155 others were wounded during the explosions.
Kabul has been on high alert since the US announced it was withdrawing troops from Afghanistan, and the Taliban fighters have stepped up operations against government forces.
President Ghani blamed the attack on the Taliban, saying in a statement that “by escalating the illegitimate war and violence, the Taliban have once again shown that they are not only reluctant to resolve the current crisis peacefully and fundamentally, but by complicating the situation, sabotaging the opportunity for peace”.
But a Taliban spokesman denied any involvement in the attack.
The attack sparked national and international reactions, urging parties to the conflict to resolve issues through negotiations and avoid targeting civilians and public places.