The brother-in-law of opposition Congress party leader Rahul Gandhi appeared before the Enforcement Directorate (ED) on Wednesday, in a case that has political undertones months before a national election.

Vadra visited the offices of the ED in a case relating to alleged ownership of 1.9 million pounds of undisclosed assets abroad, one of his lawyers, who declined to be named told.

The lawyer declined to comment further on the specifics of the case, while Vadra could not be reached for comment.

The ruling Bharatiya Janata Party (BJP) led by Prime Minster Narendra Modi has made a crackdown on corruption – in particular involving the opposition Congress party – a major issue in the run-up to nationwide polls that must be held by May.

Vadra is married to Gandhi’s sister, Priyanka Gandhi Vadra, who last month entered active politics amid a tightening race between the BJP and Congress. She accompanied him in a car to the Enforcement Directorate’s offices on Wednesday.

Abhishek Manu Singhvi, a spokesman for the Congress party, said Vadra had answered the summons from the agency “in a spirit of cooperation”, dismissing the BJP’s charges.

A well-connected New Delhi-based businessman, Vadra has previously faced scrutiny over an alleged series of land transactions with Indian real estate developer DLF in 2014, which were used as ammunition by the BJP to attack Congress and the Nehru-Gandhi dynasty, that has dominated the party during its decades in power post-Independence.