(S (S (PP (IN In) (BASENP (DT a) (JJ unrelated) (NN incident))) (COMMA ,) (S (BASENP (DT a) (JJ civilian) (NN helicopter)) (VP (VBD crashed) (PP (IN near) (BASENP (DT the) (NNP Danziger) (NNP Bridge)))))) (PERIOD .))