(S (S (S (NP (BASENP (NNS Owners)) (PP (IN of) (BASENP (DT the) (NN coal) (NN mine)))) (VP (VBP have) (VP (VBN been) (VP (VBN detained) (PP (IN by) (BASENP (JJ local) (NN police))))))) (CC and) (S (NP (BASENP (DT the) (NN investigation)) (PP (IN into) (NP (BASENP (DT the) (NN cause)) (PP (IN of) (BASENP (DT the) (NN flooding)))))) (VP (VBZ is) (ADJP (JJ underway))))) (PERIOD .))