ED sources told PTI the agency was trying to figure out whether there was any underhand dealing with the Saradha Group besides his salary of Rs 70,000 per month which he used to receive from the tainted firm when he was a paid employee as an executive editor of 'Kalom', a Bengali newspaper.
The sources said that the ED had got some clues from him which were being verified by it.
Hassan owned the newspaper before selling off his shares to the Saradha Group at a consideration of around Rs 2 lakh, the sources said.
The other shareholders also sold their shares to Saradha, the source said.
Concurrently, the special crime branch of CBI on Tuesday again interrogated Asif Khan, editor of another Bengali daily 'Aajker Kalom' who is considered close to the Trinamool Congress leadership, in connection with the Saradha scam.
Khan, after the interrogation, told waiting reporters that he would fully cooperate in the probe.
"I was not called today, but I came on my own," he claimed.
Former police officer Rajat Mazumdar, who was a paid employee of the Saradha Group, was also interrogated by the CBI.
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