The National Investigation Agency estimates face value of fake Indian currency notes in circulation is over 1.6 billion rupees.
Such notes, believed to have been routed from Pakistan, have been seized not only from India but also from Nepal, Bangladesh, Afghanistan, Holland, Denmark, Singapore, Sri Lanka, Malaysia, Thailand and the UAE.
Police have detected only 28 to 30 per cent of fake currency actually circulating in the market, according to an estimate carried out last December.
India has identified four major players in Pakistan who sometimes use the sea route to transfer money.
Security agencies have found that the racketeers have been using migrant workers as couriers.