CBI sources said Umesh Kumar, the journalist allegedly involved in the sting operation, was questioned by the agency for nearly two and half hours at the CBI headquarters here.
"CBI has asked me to provide raw footage of the sting which I will give tommorow," Umesh said, coming out of the CBI office.
The sources said the preliminary enquiry was registered on the instructions of the state government which is under President's rule and further notification from the central government.
Congress had alleged that the "dirty tricks department" of BJP president Amit Shah is at work, while the saffron outfit had demanded "immediate dismissal" of the Rawat government.
"The sting CD being shown on news channels is fake. The reputation of the man behind it who is associated with a private news channel is not hidden from anyone. His antecedents must be probed," Rawat had said.