(S (S (NP (BASENP (DT A) (JJ small) (NN group)) (PP (IN of) (BASENP (QP (RB about) (NN 15)) (NNS police) (NNS officers)))) (VP (VBD awaited) (NP (BASENP (DT the) (NN arrival)) (PP (IN of) (BASENP (DT the) (NN group)))))) (PERIOD .))