In what could spell more trouble for Andhra Pradesh chief minister and Telugu Desam Party (TDP) chief N. Chandrababu Naidu, Telangana Home Minister Nayani Narasimha Reddy on Wednesday alleged that Naidu was the "key person" in the issue of the Revanth Reddy cash-for-votes case.Narasimha Reddy also added that the state had proof to nail Naidu in the form of Telephone conversations that the TDP chief had with his legislators. All eyes are on the next move of the state's Anti-Corruption Bureau (ACB).TDP MLA Revanth Reddy was nabbed while offering Rs 50 lakh to a nominated member of the assembly as part of a Rs 5-crore deal to make him vote for the TDP-BJP candidate in election to the Telangana legislative council (Upper House).The ACB has sought the custody of the TDP MLA who was arrested on Sunday.The investigators are likely to interrogate him about the TDP chief's alleged role in the scandal. The ACB sleuths may question him about his "boss", whom he repeatedly mentioned during the talk with the nominated MLA. The conversation was recorded on a spy camera.Read - This video is the reason the TRS wants 'boss' Naidu to be booked in Revanth Reddy caseThe Telangana home minister claimed that Naidu spoke to nominated MLA Elvis Stephenson over phone and that police have audio record of the alleged conversation. He also said he has have evidence that Naidu spoke to some MLAs of the Telangana Rashtra Samithi (TRS) for a similar reason.He also added that there was a growing demand from public that Naidu should be made the main accused. "In the coming days, there will be dramatic developments," Narasimha Reddy told reporters in Warangal on Wednesday.Revanth Reddy, a member of the Telangana assembly and his two aides were arrested by the ACB at the residence of Stephenson, who represents the Anglo-Indian community in the Telangana assembly. The trap was laid on a complaint by the nominated MLA.The next day, a city court sent Revanth and two others to judicial custody for 14 days. TRS leaders, including Chief Minister K. Chandrasekhar Rao's daughter K. Kavitha, a member of parliament, have demanded that Naidu should be made an accused in the case.Telangana's Irrigation Minister Harish Rao, who is Chandrasekhar Rao's nephew, has described Naidu as the mastermind behind the bid to buy votes for the TDP-BJP combine in the council poll. Information Technology Minister K. Tarakarama Rao, who is son of the chief minister, has said law will take its own course. "If there is prima facie evidence, there is no reason why Naidu should not be included," said Tarakarama Rao. He said the ACB will go deep into the case to find out the mastermind.The trap for Revanth Reddy was reportedly laid after TRS leaders got a wind of the attempts being made by Naidu to woo some disgruntled TRS MLAs to vote for the TDP-BJP candidate. Sources claim that Naidu, who last week was elected the TDP's national president, wanted to take revenge on the TRS for encouraging defections in the TDP in Telangana. Five TDP lawmakers have defected to the TRS during last one year.Read - Defection Raj: From 63 MLAs in 2014, the TRS now has 76It was after the TRS learnt about Naidu's attempt to woo some of its MLAs that KCR went to the extent of threatening dissolution of the assembly if the TRS failed to win all its five seats to the council. TRS sources said this was a threat to some MLAs who were in touch with TDP leaders.The YSR Congress Party, the main opposition party in Andhra Pradesh, has also demanded that Naidu be made an accused in the case. YSR Congress president Y.S. Jaganmohan Reddy even met E.S.L. Narasimhan, who is governor of both the states, to make the demand.The Congress party in both Telangana and Andhra Pradesh has demanded a thorough probe into Naidu's role.The TDP has hit back at the YSR Congress, saying it entered into a conspiracy with the TRS to target the party and that they would fight the case and stick with Revanth. For the TDP chief and his party, this might even be the end of the road in Telangana.Inputs from IANS