The CBI on Tuesday conducted searches in Mumbai, Delhi, Gurugram and Chennai, including at the residences of former Union minister P Chidambaram and his son Karti.
The searches are in connection with alleged criminal misconduct in grant of investment approval by the FIPB.
The CBI had recently registered a case regarding Foreign Investment Promotion Board (FIPB) clearance given to a company in which it is alleged that favours were given when P Chidambaram was the finance minister.
A total of at least 14 locations in Chidambaram's home city of Chennai were searched by the CBI, TV channel reported.
Commenting on raids, Chidambaram accused the government of using the CBI and other agencies to target his son and his friends.
"The government, using the CBI and other agencies, is targeting my son and his friends. The government's aim is to silence my voice and stop me from writing, as it has tried to do in the cases of leaders of Opposition parties, journalists, columnists, NGOs and civil society organizations. All I will say is, I shall continue to speak and write," Chidambaram said in a statement after the raids.
"FIPB approval is granted in hundreds of cases. The five Secretaries who constitute the FIPB, the officials of the FIPB Secretariat and the competent authority in each case are the public officials. There is no allegation against any of them. There is no allegation against me. Every case was processed according to law and approval was granted or refused in accordance with the recommendations of the FIBP consisting of five Secretaries to the Government of India," the former finance minister said.
Enforcement Directorate is investigating various aspects of the FIPB approval given in the Aircel-Maxis deal case, including the role of former finance minister P Chidamabarm, under anti-money laundering laws.
"Investigations under the Prevention of Money Laundering Act (PMLA) are going on in respect of FIPB approval given to Aircel-Maxis by the then finance minister (Chidamabaram).
"In the case, foreign inflow was Rs 3,500 crore (approximately) whereas as per government policy and FIPB guidelines competent authority was Cabinet Committee of Economic Affairs for any inflow above Rs 600 crore," the agency said in a statement last month.