(S (S (BASENP (DT The) (ADJP (RBS most) (JJ serious)) (JJ such) (NN incident)) (VP (VBD involved) (NP (NP (BASENP (DT the) (NNP October) (NN 2005) (NN crash)) (PP (IN of) (BASENP (DT a) (JJ Russian) (NN jet) (NN fighter)))) (PP (IN in) (BASENP (NNP Lithuania)))))) (PERIOD .))