(S (S (NP (BASENP (NNS (NN Police))) (PP (IN in) (NP (BASENP (NNP Melbourne)) (COMMA ,) (BASENP (NNP Australia))))) (VP (VBP are) (PP (IN on) (NP (BASENP (DT the) (NN hunt)) (PP (IN for) (NP (BASENP (DT a) (NN gunman)) (SBAR (WHNP (WP who)) (S (VP (VP (VP (VP (VBD killed) (BASENP (DT a) (NN man))) (CC and) (VP (VBD injured) (BASENP (NN two) (NNS others)))) (PP (IN in) (NP (BASENP (DT the) (NN city) (POS 's)) (BASENP (JJ central) (NN business) (NN district))))) (BASENP (DT this) (NN morning))))))))))) (PERIOD .))