The Central Bureau of Investigation raided up to 16 premises of former Union minister P Chidambaram and his son Karti Chidambaram on Tuesday. The searches were reportedly carried out held in connection with the foreign investments received by a media firm.

The raids were conducted at locations in Mumbai, Delhi, Gurugram and Chennai. They come days after the agency filed an FIR against Karti Chidambaram and INX Media. The Names of Indrani Mukerjea and Peter Mukerjea, among others, were also included in its complaint for criminal conspiracy and cheating, reported Times Now.

CBI officials told NDTV that they were investigating the charge that Karti Chidambaram’s company received Rs 10 lakh from INX Media, which got a Foreign Exchange Promotion Board clearance for Rs 4 crore, but had actually received Rs 305 crores. INX Media was then owned by Peter Mukerjea and his wife Indrani. The two are now being tried for the murder of Indrani Mukerjea’s daughter, Sheena Bora.

The Enforcement Directorate had earlier alleged that Chidambaram helped the media firm get the illegal FIPB clearance, according to The Indian Express.

Reacting to the raids, Chidambaram called it a government ploy to target his son. “The government wants to silence my voice,” claimed the former finance minister. “The government wants to stop me from writing, as it has tried to with leaders of Opposition parties, journalists, columnists, NGOs and civil society members.” Chidambaram issued a statement, saying, “FIPB approval is granted in hundreds of cases... Every case was processed according to law and approval was granted or refused in accordance with the recommendations of the FIPB consisting of five Secretaries of the Government of India.”

Congress spokesperson Tom Vadakkan said, “The attempt is to grab headlines and create a perception. Why no action for three years?” NDTV reported. Party leader KR Ramasamy dismissed reports that the former minister was guilty of any illegalities. “These raids are politically motivated,” Ramasamy said.

Last month, the Enforcement Directorate had issued a showcause notice to Karti Chidambaram and a firm linked to him. This was in connection with alleged violations of the Foreign Exchange Management Act of around Rs 45 crore.

Karti Chidambaram is also accused of facilitating bribes in the Aircel-Maxis transaction. The Aircel-Maxis deal is part of the bigger 2G spectrum scam. In August 2015, the ED had issued summons to two directors of a firm linked to Karti Chidambaram after an investigation revealed that Rs 26 lakh had allegedly been sent from the firm to Aircel Televentures. A firm owned by Karti Chidambaram also allegedly received payments from Maxis after the deal was executed.