The Cauvery water dispute between Karnataka and Tamil Nadu took yet another ugly turn today, wit Tamil Nadu filing a contempt petition in the Supreme Court against Karnataka which names Chief Minister S M Krishna as one of its respondents for defaulting on water releases. The Centre also stepped into the ring, with Union Water Resources Minister Arjun Charan Sethi writing to Krishna that Karnataka should abide by the September 8 decision of the Cauvery River Authority, according to which the state had to release 0.8 tmcft of water to Tamil Nadu daily.