Nadkarni, ASG of the central government, on Monday accused Goa Chief Minister Pramod Sawant of being part of a purge against the Parrikar family and aides, after the latter's death in March.
"By saying that the Bharatiya Janata Party (BJP) is in a witch-hunt mode, Nadkarni is actually backing the Congress claim. We have been maintaining that Chidambaram was arrested as part of the BJP leadership's witch-hunt," said Goa Congress spokesperson Trajano D'Mello.
Chidambaram is in the Central Bureau of Investigation (CBI) custody in connection with the INX Media money laundering case.
Nadkarni, who holds legal briefs of BJP-led governments of Maharashtra and Uttar Pradesh in the Supreme Court, had said a witch-hunt was on against aides, even relatives, of Parrikar.
He claimed several top officials and aides, including him, had become victims of the political witch-hunt. Nadkarni was stripped of the Goa government brief after Sawant became the Chief Minister.
Citing a specific case, Nadkarni said, the father-in-law of Parrikar's son Utpal, who headed the radiology department of a government-run top hospital, had been terminated after Sawant came to power.
However, state BJP chief Vinay Tendulkar has denied reports of a purge of the Parrikar aides from the government and other positions.
( With inputs from IANS )