(S (S (PP (VBG Following) (NP (BASENP (DT an) (NN incident)) (PP (IN at) (BASENP (NNP Glasgow) (NN airport))))) (COMMA ,) (S (BASENP (NNP Home) (NNP Secretary) (NNP Jacqui) (NNP Smith)) (VP (VP (VBD announced) (NP (NP (NP (BASENP (DT the) (NN elevation)) (PP (IN of) (NP (BASENP (DT the) (NNP UK) (POS 's)) (BASENP (JJ national) (NN threat) (NN level))))) (PP (IN from) (QT (DQL ``) (ADJP (JJ Severe)) (DQR '')))) (PP (TO to) (QT (DQL ``) (ADJP (JJ Critical)) (DQR ''))))) (COMMA ,) (S (VP (VBG indicating) (SBAR (IN that) (S (BASENP (DT an) (NN attack)) (VP (MD could) (VP (VB be) (VP (VBN expected) (QT (DQL ``) (ADVP (RB imminently)) (DQR '')))))))))))) (PERIOD .))