Telangana Congress working president and former legislator A Revanth Reddy Tuesday appeared before the Enforcement Directorate (ED) in connection with the cash-for-vote case.
The Congress leader, who was recently served a notice by the ED, appeared before it and was quizzed by the probe agency's officials for several hours.
In 2015, Reddy, then in the Telugu Desam Party (TDP), was caught while allegedly trying to give a bribe to a nominated lawmaker to vote for his party's nominee in the Telangana Legislative Council polls.
The Telangana Pradesh Congress Committee working president later accused caretaker Chief Minister K Chandrasekhar Rao of "targeting" him by using investigating agencies.
Mr Reddy alleged that Mr Rao had misused his powers in the assembly elections.
"He (Rao) is making use of investigating agencies in targeting me but he cannot intimidate me. Four-year- old case is being dragged on intentionally to trouble me", the Congress leader said.
"I have appeared before the ED today. They have questioned me on many things but I cannot reveal the details. I have to appear before the ED officials on Wednesday. My fight against KCR (as Rao is also referred to) will continue," Mr Reddy told reporters.
On May 31, 2015, Mr Reddy, then in the TDP, was caught by the Anti-Corruption Bureau (ACB) while allegedly paying a bribe of Rs 50 lakh to Elvis Stephenson, a nominated MLA, for supporting TDP nominee Vem Narendar Reddy in Legislative Council elections held on June 1, 2015.
The ACB had then arrested Mr Reddy and others. Later, he and all the others arrested were granted bail.
Another accused in the cash-for-vote case and Mr Reddy's aide R Uday Simha had also recently appeared before the ED.
In October 2018, Mr Reddy had appeared before the Income Tax department and was questioned in connection with the searches conducted earlier at his residence and offices.