New Delhi, Oct 16 (ANI): Communist Party of India (Marxist) leader Sitaram Yechury on Wednesday said that the country needs a thorough and a complete probe in the coal scam case to ensure that the guilty are punished. Yechury said that the CPI (M) has been demanding a complete and a thorough investigation into the entire scam on the basis of what the CAG report has said. To a poser on whether he saw any link in between the BJP and the Coal Secretary, Yechury said all attempts are being made to conceal the truth in this case.