BJP leader Subramanian Swamy has asked Prime Minister Manmohan Singh to take necessary steps to stop the "witch-hunt" against Justice (retd) A K Ganguly in the case of his alleged sexual harassment of a law intern.

In a letter to Singh, he said there has to be an impartial investigation to determine the truth as to what happened in the "media-driven episode of a former intern alleging 'unwelcome' behaviour' by the former Supreme Court judge.

Swamy said it was "extremely important at this juncture to get an investigation completed before any precipitate action is taken merely to make out Justice Ganguly guilty without an opportunity of being heard".

He noted that the statutes governing the chairperson's tenure at the West Bengal Human Rights Commission make it clear that the chairperson can be removed from the post only if he or she is convicted.

The former law intern has hit back at Justice Ganguly for denying the charges and hinted that she may file a police complaint.