The Rajasthan Anti-Corruption Bureau on Monday issued notices to dissident Congress MLAs Bhanwarlal Sharma and Vishvendra Singh, asking them to appear before it within three days for investigation into an alleged plot to topple the state government.
The ACB had registered an FIR against Bhanwarlal under the Prevention of Corruption Act on July 17 in connection with the audio tapes, which allegedly indicate a plot to bring down the Congress government in the state.
Vishvendra Singh, who was earlier removed from the state Cabinet, has too been summoned for investigation with regard to the audio tapes.
"We have issued them notices today, asking them to appear within three days," an ACB official said.
The FIR was registered on the complaint of state government chief whip Mahesh Joshi, who had produced three audio tapes.
In two of the tapes, MLA Bhanwarlal Sharma is allegedly heard talking to one Sanjay Jain and Gajendra Singh regarding the "conspiracy" and "amount".
Citing the audio clips on social media, the Congress had demanded the resignation of Gajendra Singh Shekhawat from the Union Cabinet, saying he has no moral authority to continue when he is heard on audio clips that suggest a BJP conspiracy to topple the government in Rajasthan.
However, the FIR does not identify "Gajendra Singh" referred to the clip as Union minister Mr Shekhawat, a senior BJP leader from Rajasthan.
The third audio tape is allegedly having a conservation between two people but no name appears on it.
However, ACB sources said one voice resembles to that of Vishvendra Singh, therefore a notice was issued to him as well.
The Special Operations Group (SOG) of the Rajasthan Police has also registered two FIRs in connection with the audio tapes and has arrested Sanjay Jain, referred to as a BJP leader by the Congress, a charge denied by the saffron party.
The SOG has also issued a notice to Union Minister Gajendra Singh Shekhawat in this regard and trying to locate Congress MLA Bhanwarlal for investigation into the case.
The Congress Party had earlier suspended the primary membership of Vishvendra Singh and Bhanwarlal Sharma after the audio tapes surfaced.