It is an unprecedented battle between two chief ministers - Andhra Pradesh Chief Minister Chandrababu Naidu has filed cases of defamation today against his Telangana counterpart K Chandrasekhar Rao after a tape emerged that allegedly has audio of him backing a cash-for-votes scandal in which a TDP legislator was arrested last week. Mr Naidu's office has denied it is his voice on the tape and are accusing the TRS government of Telangana of tapping their phones - a charge the TRS is denying. We spoke to Parakala Prabhakar, Advisor to Andhra government.