Nasir and I are in the city of Quetta, sitting in the waiting room of the largest military hospital in the province of Balochistan. His 14-year-old son Mohammad Ahmad told him he was flung across the army school bus in a bombing in Khuzdar, a few hours' drive away.

A suicide attack on a school bus in southwestern Pakistan killed three students of a military-run school on Wednesday, officials said, in the latest attack that underscores the deteriorating security situation in the region.

Two more schoolgirls, injured in the recent terrorist attack on a school bus in Khuzdar, succumbed to their wounds, bringing the total number of student martyrs to eight, security officials confirmed on Saturday.