(S (S (BASENP (NN Security) (NNS officials)) (VP (VBP say) (SBAR (S (BASENP (DT the) (NN bomber)) (VP (VP (VP (VBD drove) (BASENP (PRPD his) (NN vehicle))) (PP (IN into) (BASENP (DT the) (NN convoy)))) (PP (IN on) (NP (BASENP (DT the) (NNP Jalalabad) (NN road)) (COMMA ,) (SBAR (WHNP (WDT which)) (S (VP (VBZ is) (ADJP (JJ notorious) (PP (IN for) (S (VP (VBG being) (NP (BASENP (DT the) (NN scene)) (PP (IN of) (NP (BASENP (JJ frequent) (NNS attacks)) (PP (IN by) (BASENP (DT the) (NNP Taleban)))))))))))))))))))) (PERIOD .))