(S (S (BASENP (NNP ETA)) (VP (VP (VP (VBD called) (BASENP (DT the) (NN cease-fire))) (PP (IN in) (BASENP (NNP March) (NN 2006)))) (CONJP (COMMA ,) (CC but)) (VP (VP (VBD grew) (ADJP (JJ frustrated) (PP (IN with) (NP (BASENP (DT a) (NN lack)) (PP (IN of) (NP (BASENP (NN government) (NNS concessions)) (PP (IN in) (S (VP (VBG ensuing) (BASENP (NN peace) (NNS talks))))))))))) (CONJP (COMMA ,) (CC and)) (VP (VP (VP (VP (VP (VBD set) (PRT (RP off))) (BASENP (DT a) (JJ huge) (NN bomb))) (PP (IN in) (NP (BASENP (DT a) (NN parking) (NN area)) (PP (IN at) (NP (BASENP (NNP Madrid) (POS 's)) (NN airport)))))) (PP (IN on) (BASENP (NNP December) (NN 30)))) (COMMA ,) (S (VP (VBG killing) (BASENP (NN two) (NNS people)))))))) (PERIOD .))