During the preliminary enquiry stage, the CBI had questioned Harish Rawat and Umesh Sharma.
The CBI has filed an FIR against former Uttarakhand chief minister Harish Rawat and his then cabinet colleague Harak Singh Rawat, who is now a member of the state's BJP-led government, for alleged attempts of horse trading in 2016, which was caught on tape by an editor of a news channel, officials said on Wednesday.
The agency had conducted an preliminary enquiry into the alleged horse trading attempt on March 23, 2016 when the state was under President's rule.
It sent the tape to the Forensic Science Laboratory, Gandhinagar in Gujarat for analysis which opined that the recording was "genuine" and there was no evidence of any
"addition/deletion/insertion/tampering/morphing" in the video files.
The video purportedly showed the Congress leader discussing money to win back the support of disgruntled MLAs who had crossed over to the BJP so that he could get back to power.
Recently, the Uttarakhand High Court gave its nod to the CBI to go ahead with its investigation in the case and lodge an FIR against Mr Rawat after the agency submitted a report in a sealed cover on the preliminary inquiry.
Besides Harish Rawat and Harak Singh Rawat, who joined the BJP later and is now a minister in the Trivender Singh Rawat-led cabinet, the CBI has also booked editor-in-chief of Noida-based Samachar Plus channel Umesh Sharma, who had purportedly carried out the sting operation in the airport lounge, the officials said.
The CBI has slapped Indian Penal Code section pertaining to criminal conspiracy and bribery provisions of Prevention of Corruption Act on the trio.
After the video surfaced, the Centre handed over the probe to the CBI.
During the preliminary enquiry stage, the CBI had questioned Harish Rawat and Umesh Sharma.