The Bharatiya Janata Party (BJP) on Sunday asked Congress president Sonia Gandhi to explain how her son-in-law Robert Vadra managed to amass Rs. 300 crore in a few years with an investment of Rs. 1 lakh; that, too, at a time when the country was in an economic slow down.

Billing it the “Vadra ‘get-rich-quick’ model”, BJP senior leader Ravi Shankar Prasad said the party had a slew of questions on the land deals struck by Mr. Vadra in collusion with the Congress governments of Haryana and Rajasthan.

Asked why the BJP had not filed any case against Mr. Vadra in Rajasthan — now that the party has been able to wrest the State from the Congress in December — Mr. Prasad said, “Nothing shall be done with vendetta. This is not a witch-hunt. Enquiry is on; the law will take its own course.”

Stepping up the party’s campaign against Mr. Vadra days after his wife and Ms. Gandhi’s daughter Priyanka Vadra sought to counter the allegations against him, the BJP has brought out a booklet and a film in this regard. The film — that takes a fleeting dig at the political dynasties of the Dravida Munnetra Kazhagam and the Samajwadi Party — is a dramatised version of the allegations made in the booklet.

Of the view that only Ms. Vadra has been defending him and the Congress has not responded properly to the allegations, Mr. Prasad said the Congress president and her son Rahul Gandhi should reply to the BJP’s questions as without their patronage Mr. Vadra would not have been able to buy and sell land in the two States the way he did.

According to the BJP, the business model of Mr. Vadra is “kleptocratic rentiering from discretionary licensing and change in land use permissions of the government”. This is a text-book case of crony capitalism — a charge leveled often against BJP’s prime ministerial candidate Narendra Modi — under the patronage of the family, Mr. Prasad added.

“They must come clean on the land deals of Mr. Vadra and his companies,” Mr. Prasad said, adding that he had broken a series of laws including Sections 9 and 13 of The Prevention of Corruption Act, 1988; Sections 417, 467, 468, 471 and 120B of the Indian Penal Code; Section 82 of the Registration Act, 1908; and Sections 271(5) and Section 628 of the Companies Act, 1956. Mr. Vadra is also in violation of the Haryana Ceiling on Land Holdings Act, 1972, as he and his family have more than 147 acres as against the permissible limit of 54 acres.

Accusing the Gandhi family of “destroying institutions, blighting the honest and rewarding the corrupt”, the BJP pointed out that the officer who handled issues pertaining to land use in the Haryana Chief Minister’s Office was made member of the Union Public Service Commission post-retirement. Normally officials who retire in the post of Secretary are made UPSC members but this individual — who Mr. Prasad refused to name despite questions about his identity — was of Additional Secretary rank at the time of retirement.