One killed in blast at security checkpoint in northwestern Pakistan . Explosion occurred in the Shangla district in the volatile Swat Valley . A phone call tipped officials to Saturday 's attack , general reports . The attacks will not deter Pakistan from launching an offensive in South Waziristan , the Interior Ministry said . Swat Valley has been scene of clashes with Taliban militants .
One killed in blast at security checkpoint in northwestern Pakistan . Explosion occurred in the Shangla district in the volatile Swat Valley . A phone call tipped officials to Saturday 's attack , general reports . Swat Valley has been scene of clashes with Taliban militants .