After the CBI raided the residence of P. Chidambaram, the former Union home minister issued a statement, saying that the agency "found nothing and there was no seizure but the timing was interesting".
He said, "This morning, a CBI team searched my residence at Chennai and my official residence at Delhi. The team showed me an FIR in which I am not named as an accused.
"The search team found nothing and seized nothing.
"I may point out that the timing of the search is interesting."
Earlier, the Congress defended Chidambaram and alleged that he was being maligned.
Taking to Twitter, Congress General Secretary Randeep Surjewala said: "Mr. @PChidambaram_IN is a Nationalist & a Patriot, whose commitment to the country is unquestionable."
He alleged that the CBI was planting a story to malign him. "To plant source based preposterous allegations against a former Home Minister & Finance Minister by CBI reflects the lowest ebb in political discourse."
Reacting to the raids, Karti Chidambaram slammed the agency saying that he has lost count of the number of searches, adding "must be record".
"I have lost count, how many times has it been? Must be a record," he tweeted.
The Central Bureau of Investigation (CBI) was conducting raids at nine locations belonging to P. Chidambaram and his son Karti Chidambaram in connection with a fresh case of Chinese visa issued for illegal gratification.
According to information, the federal probe agency was conducting raids at Odisha, Mumbai, Karnataka, Delhi and Chennai.