Bhopal, June 26 (ANI): Congress supporters staged a sit-in protest accusing leaders of the ruling BJP being involved in the Madhya Pradesh Professional Examination Board or Vyapam scam. Congress workers demanded a probe to be conducted by the CBI on the scam. Meanwhile, student body, National Student's Union of India also protested against the scam. Congress leader Satyadev Katare also accused Madhya Pradesh Chief Shivraj Singh Chouhan of being involved in the employment scam. He showed documents of the Public Service Commission Examinations to prove that Chouhan's niece was appointed as Deputy Collector by illegal means and also said that the former had changed rules to destroy evidence of irregularities.