Heavy security was in place here Thursday in view of a strike called by various parties, including the opposition Congress, to protest the Vyapam scam in Madhya Pradesh.Various shops were closed in capital Bhopal and adjoining cities early Thursday. Few public transport buses plied.The Congress is demanding the CBI probe into the matter under supervision of Supreme Court and also an investigation on the agencies earlier probing the scam. The party has assured that the strike will be a peaceful one.A 40-member team under supervision of CBI Joint Director R.P. Aggarwal initiated its probe into the Vyapam scam on Monday. Vyapam (Vyavsayik Pariksha Mandal) conducts recruitment and entrance exams not done by the Madhya Pradesh Public Service Commission. The Vyapam scam came to light in 2013 and has since assumed mind-boggling proportions, leading to the arrest of nearly 2,100 people. Nearly 40 people linked in some way to the scam have also died.