The attacker blew himself up close to a bus in the terminal located near a busy market in Kohat, located 60 km from Khyber-Pakhtunkhwa capital Peshawar.
State-run Pakistan Television Corporation put the death toll at 15 while local provincial legislator Kalb-e-Hasan told the media that 17 people were killed. Twenty others were injured in the blast, which occurred on the first day of the Islamic holy month of Muharram.
Authorities have put in place strict security arrangements across Pakistan as sectarian and militant violence has occurred during the month in past years. "It was a suicide blast and we have found the head of the bomber," said Dilawar Khan Bangash, Kohat district police chief. Other officials said several of the injured were in a serious condition.
Witnesses said they had seen human flesh and bodies lying at the site of the blast.
The bomber struck at about 1 pm, when the bus terminal was crowded with people travelling to the adjoining Kurram and Orakzai tribal regions. The blast destroyed the bus targetted by the bomber and damaged several other vehicles. The bodies and injured were rushed to two nearby hospitals.
Authorities declared an emergency at all hospitals in Kohat and staff and doctors were recalled for duty. No group claimed responsibility for the attack.
This was the second suicide attack in northwest Pakistan in three days. On Monday, 50 people were killed and over 100 others injured when two suicide bombers disguised as policemen struck a government compound in Mohmand tribal region.
The Taliban claimed responsibility for Monday's attack.
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