In yet another incident of explosion in Pakistan, at least five police personnel have been killed and more than 21 injured after a powerful blast targeted security officials in the northwestern region of the country. According to local media reports, the bomb exploded close to a police patrol in Dera Ismail Khan city.In yet another incident of explosion in Pakistan, at least five police personnel have been killed and more than 21 injured after a powerful blast targeted security officials in the northwestern region of the country. According to local media reports, the bomb exploded close to a police patrol in Dera Ismail Khan city.