The bus driver and his assistant were among those killed in the attack in Khuzdar district of Balochistan province, on the way to a school that caters to the children of army personnel and civilians living in the area.
Prime Minister Shehbaz Sharif accused arch-rival India of backing the militants that carried out the attack, coming almost two weeks after the two sides settled a ceasefire to end their most serious conflict in decades.
“Terrorists operating under Indian patronage attacking innocent children on a school bus is clear evidence of their hostility,” his statement added.
The military also said in a statement that the attack was “planned and orchestrated” by India.
The nuclear-armed neighbours regularly trade accusations that the other supports militant groups operating in their territory.
The four-day conflict earlier this month was sparked by an attack on tourists in Pahalgam in Indian-administered Kashmir that India accused Pakistan of backing, for which it took revenge.
Pakistan denied any involvement in the attack.
New Delhi’s foreign affairs ministry said in a statement that “India rejects the baseless allegations,” adding that it was “second nature” for Pakistan to blame India.
No group has yet claimed responsibility for Wednesday’s bombing.
Sarfraz Bugti, the chief minister of Balochistan province, said four children, the bus driver and his assistant were killed. (AFP)
