The banned Tehreek-i-Taliban Pakistan (TTP) has claimed responsibility for the Peshawar attack in a statement sent to media outlets by its spokesman.
According to the SP, the suicide attacker riding a motorcycle targeted the FC convoy when it was travelling from its camp in Hayatabad to the headquarters in Qila Bala Hisar.
The vehicle was moving when the blast occurred, he said.
SSP (operations) Sajjad Khan said 10-12 kilograms of explosives were used by the bomber, who was riding a Honda CG125 bike.
Two security personnel including a major were martyred in the loud explosion, while a third FC official succumbed to his injuries at the hospital.