The former Chairman was arrested in Lucknow following a complaint by a woman who alleged that Ram Mohan had raped her and had created a obscene video of her five years ago.
Additional Director General (Law and Order) Brijlal told reporters that a rape case was registered against Garg at Khair police station in Aligarh.
"The victim had earlier lodged a complaint of rape against the former BSP leader and submitted CDs and phone call records as evidences," the ADG said.
Ruling BSP reacted to the arrest and said, that Garg had resigned from the party last year and he was not even a primary member of the party.
"All the charges against me are baseless...It's a political conspiracy against me," Garg told reporters at Gomti Nagar police station.
OneIndia News (With inputs from Agencies)