The Taliban has said that it targeted the military-run school in Peshawar this morning because the army "targets our families".
"We selected the army's school for the attack because the government is targeting our families and females," said Taliban spokesman Muhammad Umar Khorasani, according to Reuters. "We want them to feel the pain."
More than 80 children have been killed in the attack.
The boxer said it was the "least he could do" and even donated the £30,000 shorts he wore in his last fight against Devon Alexander.
Pakistan have released intelligence of the final conversations by the Taliban attackers responsible for the Peshawar school massacre.
As forensics examine the evidence in the school were 148 people, mainly children, where killed, students prepare to return to the classroom.