(S (S (S (BASENP (DT A) (FW tsunami) (NN alert)) (VP (VBD was) (VP (ADVP (RB initially)) (VP (VBN issued) (PP (VBG following) (BASENP (DT the) (NN tremor))))))) (CONJP (COMMA ,) (CC but)) (S (BASENP (PRP it)) (VP (VBD was) (VP (VBN retracted) (ADVP (RB shortly) (RB afterwards)))))) (PERIOD .))