In West Bengal CBI on Thursday filed charge sheet against Sudipta Sen and two of his companies in Sardha Chit Fund Scam. The investigating agency probing the scam filed the charge sheet in the court of Additional Chief Judicial Magistrate of Alipore keeping the provision for further investigations open.<br/><br/>The two companies are Sardha Construction Company Private Limited and Sardha Realty India Limited. Meanwhile, the CBI on Thursday also interrogated the West Bengal Minister Mr. Madan Mitra at SSKM Hospital in Kolkata in connection with the scam. Mr. Mitra was arrested by the CBI in December last year. A local court has recently given permission to CBI to interrogate the ailing Minister at hospital.