NEW : Pakistan 's Prime Minister Nawaz Sharif condemns attack , cancelled Davos trip . NEW : the killing of Maulana Waliur Rehman , commander of TTP South Waziristan , who was killed on May 29 , 2013 , in a U.S. drone strike in Miranshah , '' TTP spokesman Shahidullah Shahid said . Main Pakistani Taliban faction claims responsibility , calls for fresh talks . TTP spokesman : attack was to avenge the death of a Pakistani Taliban leader . The blast hit a convoy of military and civilian vehicles , killing at least 22 people .
NEW : Pakistan 's Prime Minister Nawaz Sharif condemns attack , cancelled Davos trip . NEW : Main Pakistani Taliban faction claims responsibility , calls for fresh talks . TTP spokesman : attack was to avenge the death of a Pakistani Taliban leader . The blast hit a convoy of military and civilian vehicles , killing at least 22 people .