Speaking to a television channel while being taken to the court on the expiry of his five-day CBI remand in the sting footage case, Mirza took an apparent dig at Roy for saying "he has not been seen in the video" taking money.
"He himself is seen talking over phone (in the video footage)," Mirza remarked cryptically.
Asked about Roy denying that Mirza had given money to him at his residence, the IPS officer said: "Investigation will reveal whether or not he has accepted (money)."
In an apparent reference to being brought face-to-face with Roy by the CBI, which also took the former Burdwan district Superintendent to Roy's flat for "reconstruction" of the event based on Mirza's custodial interrogation, the IPS officer said: "There has been confrontation, there has been reconstruction.
"Just because he has not been seen in the video that does not prove he hasn't taken it... The investigation will prove that. He says he has not been seen in the video. He himself is seen saying over phone (in the video footage)."
Mirza was taken to Roy's flat on Sunday for videography in the light of the clip in the footage where he was seen talking over phone with someone whom he assured that an amount of Rs 1.60 crore had been deposited at the right place.
The visit took place a day after Roy - the number one accused in the FIR filed by the CBI on the case - was grilled for two and a half hours by the sleuths.
A videographer engaged by the CBI captured every details of Mirza's movement from the lane leading to the apartment complex right upto his stay inside the flat, where was made to sit face-to-face with Roy.
"Videography was done as per identification by Mirza that the huge cash transaction took place at this place," a CBI officer had told waiting mediapersons.
Roy has dismissed the allegations, and claimed there was a conspiracy to malign him and the BJP, and that there was not a single clip in the sting footage showing him taking any money.
( With inputs from IANS )