Enforcement Directorate has questioned corporate lobbyist Nira Radia in connection with the 2G spectrum case. She was summoned to explain her role in the case. The Enforcement Directorate is looking at whether there is any violation of the prevention of Money Laundering Act in the 2008 spectrum sale. The Diretorate has also issued summons to certain telecom firms in connection with its probe into the alleged 2G spectrum scam. The CBI is already investigating the 2G scam and had told the Supreme Court that it will complete investigation and file a chargesheet within three months.