For two days, senior officials have had interactions with CBI director A.P. Singh, said a CBI source. The chargesheet is scheduled to be filed on April 25 before a special court here.

The chargesheet centres on the kickbacks paid to secure spectrum and telecom licences when the communications minister was A. Raja, who has now in jail.

“The chargesheet is about kickbacks paid by DB Realty to Kalaignar TV," said the source. "We are giving final touches to the documents."

The television station has been linked to the family of Tamil Nadu Chief Minister and DMK leader M. Karunanidhi.

The CBI is still debating if there was enough evidence to name Karunanidhi's daughter and DMK MP Kanimozhi in the chargesheet.

The CBI has found that Rs.200 crore connected with spectrum allocation travelled from DB Realty of Shahid Usman Balwa to Kalaignar TV.

The agency said the money travelled through a circuitous route through Kusegaon Realty (earlier Kusegaon Fruits and Vegetables), a DB group company and Cineyug Films Pvt Ltd.

The CBI has found that the money was transferred in the following manner:

Over Rs.200 crore was first transferred from Dynamix Realty to Kusegaon Realty. Then Rs.206 crore was moved by Kusegaon Realty to Cineyug Films. Finally, Cineyug paid Rs.214 crore to Kalaignar TV.

The investigative agency arrested Asif Balwa, younger brother of Swan Telecom's Shahid Usman Balwa and owner of Kusegaon Realty, along with co-owner Rajiv Agarwal March 29.

The agency had carried out searches on the premises of DB Realty, Kusegaon Realty and Cineyug Films in connection with the alleged transfer in Mumbai March 28.