(S (S (ADVP (BASENP (JJ Several) (NNS seconds)) (RBR later)) (COMMA ,) (S (BASENP (DT a) (NN bomb)) (VP (VP (VBZ explodes) (PP (IN near) (SBAR (WHNP (WP what)) (S (VP (VBZ appears) (S (VP (TO to) (VP (VB be) (NP (BASENP (DT the) (NN lead) (NN car)) (PP (IN of) (BASENP (DT the) (NN convoy)))))))))))) (S (VP (ADVP (RB severely)) (VP (VP (VBG damaging) (NP (BASENP (DT the) (JJ front) (NN end)) (PP (IN of) (BASENP (DT the) (NN vehicle))))) (CC and) (VP (VBG injuring) (BASENP (JJ several) (NNS civilians))))))))) (PERIOD .))