(S (S (S (BASENP (NNS Deputies)) (VP (VBD had) (VP (VBN been) (VP (VP (VBG using) (BASENP (NN cell) (NNS phones))) (S (VP (TO to) (VP (VB negotiate) (PP (IN with) (BASENP (DT the) (NNS suspects)))))))))) (COMMA ,) (SBAR (WHNP (WP who)) (S (VP (VBD were) (VP (VBG wearing) (NP (NP (BASENP (NNS masks)) (COMMA ,) (BASENP (NNS wigs))) (CC and) (BASENP (NNS coats)))))))) (PERIOD .))