Two back-to-back bombings ripped through a police training centre in Pakistan's restive north-western region today, killing at least nine security personnel and six civilians, dpa quoted officials as saying. "There were two blasts with a difference of a few minutes," said Sardar Mohammad Abbas, the top civil administrator in Bannu district. The first blast took place near the main gate of the building. That was followed by another explosion when the district police chief Iqbal Marwat arrived at the scene with a contingent of the security personnel. Abbas said that Marwat was critically wounded in the blasts, adding that it was not immediately clear whether they were suicide bombings or remote-controlled explosions. An official at Bannu's state-run District Headquarter Hospital said 15 bodies and more than 20 injured had been moved there. "Four of the injured are in critical condition," said the hospitals' senior official Hafizullah Khan. According to Khan, nine policemen and three children were among those who died. The children were offering prayers at a nearby mosque, also damaged by the blast. Bannu is 140 kilometres south-west of Peshawar, capital of North Western Frontier Province. No one claimed has responsibility for the attack, which took place near the country's militancy-plagued tribal region. Pakistan is conducting military operations against Taliban and al- Qaeda fighters in the tribal areas near the Afghan border. The militants have retaliated with a suicide campaign that has killed hundreds over the last 12 months. The bombings come amid media reports that the Taliban chief Hakimullah Mehsud recently died of the wounds sustained from a January missile attack carried out by a US pilotless aircraft. Taliban have denied the reports but Pakistan's Interior Minister Rehman Malik claimed Wednesday he had "credible information" that Mehsud had died, though that information could not lead to an official confirmation. With the Taliban denial and Pakistani officials' self- contradictory statements, Mehsud's fate remains unclear.