Ever since the Satyam fraud case became public, investigations on the matter are on and now it is found that the fixed deposit documents and other instruments detained from the offices of Satyam are fake.

Investigators from the Serious Frauds Investigation Office have taken possession of around Rs 3,300 crore of such documents and out of these fixed deposits are amounted to more than Rs 2,000 crore.

It was been noted that the letters issued to the company from the banks such as ICICI Bank, Citibank, Bank of Baroda, BNP Paribas and HDFC Bank do not even have stamps.

On investigations with the banks, most of them said that they have not issued any deposit certificates to Stayam. Further they did not tried to find out who among them held Satyam's deposits.

Meanwhile Satyam's Chief Financial Officer, Srinivas Vadlamani said that the bank deposits of the firm were handled by the director, B. Ramalinga Raju and he was directed to not look into them.

However investigators were surprised that why analysts and auditors could not trace such a malpractice being carried inside the firm.

Further the investigators said that if these bank letters were fake then they will have to spot who exactly was involved into the matter besides Satyam.

"Forgery could not have been done alone or without anyone's knowledge in the company ... there must have been a team working on this," said the investigators.

Following this scam, banks have stopped any kind of transaction with the firm. In fact some of them have also frozen the bank accounts of Satyam.