Eight persons were killed and six more injured today when unidentified gunmen attacked a bus in an area in northwest Pakistan. The gunmen targeted the bus near Mammo Khwar area on the Peshawar-Parachinar road in Hangu district of Khyber-Pakhtunkhwa. Officials said, the area has been affected by sectarian violence in recent months. No group claimed responsibility for the attack. Hangu district borders the lawless Kurram tribal region, where hundreds of people have died in sectarian clashes over the past three years. Hangu has also witnessed several attacks on Shias. The Peshawar-Parachinar road, which connects the capital of Khyber-Pakhtunkhwa and Kurram Agency, was closed for almost three years due to sectarian tension in the region. It was recently reopened to traffic after clearance by the administration. Following today's attack, authorities closed the road for all traffic.