CBI sources said the searches are being carried out at 18 places in West Bengal, one in Jharkhand and one in Odisha.
The agency is carrying out searches at official premises of the company and residential premises of managing directors and directors of the company S K Najibulla, Hasibul Haque, Sunirmal Goswami, Arindam Pal, Basudev Ghosh, Falguni Chatterjee.