Islamabad, Pakistan (CNN) -- A suicide bomber killed five people Friday in an attack on a building in Khyber Agency, Pakistan's tribal region bordering Afghanistan, a government official told CNN.
Bukhtiar Khan, a senior government official of Khyber Agency, one of the seven districts of Pakistan's volatile tribal region bordering Afghanistan, said the building in the Aka Khel area was used by militants to conduct meetings.
Khan said the suicide bomber attempted to enter the building but blew himself up when a guard at the entrance opened fire on him.
No one has claimed responsibility for the attack. However, militant groups in the area have differences and have been attacking each other for a long time, Khan said.
Militants have a strong presence in Khyber and other regions along the Afghan-Pakistani border.