Calcutta, Feb. 28 :    Calcutta, Feb. 28:  A day after arresting an executive of a share-broking firm, the police on Wednesday began a probe into a multi-crore scandal that involves rigging of several bank accounts (also known as demat accounts) maintained by investors for trading in dematerialised, or paperless, shares.. Sumer Jain, a director of Bahubali International Ltd, located in Indian Exchange Place, was produced in the chief metropolitan magistrate's court, which sent him to police custody for a week for questioning. Banibrata Basu, chief of the detective department, said a team of sleuths had been given the responsibility of investigation into what is expected to unfold as a major financial scandal. 'We are not aware of another instance of such an organised financial crime in recent times. Jain and his associates amply prove that demat accounts of shares with banks , so far believed foolproof, are easy pickings,' said Basu. The police investigation was prompted by a complaint lodged by Timir Baran Roy, resident of New Barrackpore, alleging that 300 shares he held in an infotech company had moved out of his demat account with a foreign bank without his authorisation. Basu said the investigation led the police to Jain, who was found to be maintaining several fictitious demat accounts with the foreign bank named by Roy in his complaint, as well as with several nationalised banks. After collecting evidence of the alleged cheating by Jain and reconstructing the sequences of tampering with Roy's demat account, the detectives stumbled upon several other cases where Jain and his associates had defrauded unsuspecting citizens of their shares in various companies. Jain, in collusion with some bank officials, municipal officers and staff of the defrauded individuals, had been making a tidy packet for himself over the past few years by bribing, forging papers and lying to official agencies. Among the defrauded individuals are doctors, businessmen, legal personalities and housewives.