Income Tax officials plan to seek Interpol's help to question the Brazil national who allegedly gave international bills of exchange worth Rs 28,000 crore to commodity broker T M Ramalingam. The officials got the Brazilian man's name and address from a diary seized from Ramalingam's house in Dharapuram near Tirupur.

The I-T officials had earlier clarified that what they seized from the Dharapuram man on December 31 were not US treasury bonds as suspected, but international bills of exchange.

Ramalingam on Friday last told investigators about his Brazilian contact. "We have a rough idea about the man. Ramalingam claimed he exchanged gold bonds worth $5 billon to buy the international bills of exchange but we are looking into how he procured the gold bonds," an officer said.

"We passed on crucial information about the Brazilian, including his name and address that we got from a diary in Ramalingam's house, to the Interpol officials through the ministry of external affairs and asked them to probe his background. We suspect that he could be acting as a 'hawala' agent for a big name in this country and that person directed him to hand over the bills of exchange to Ramalingam," the officer said.

Ramalingam was questioned by deputy directors (investigation) Anbu Selvam and Sampath Kumar under the supervision of S Murali Mohan, IT additional director (investigations), Murali Mohan later told reporters that the inquiry was still on, and that Ramalingam had given different versions during each round of questioning. "We have seized five international bills of exchange from him. Each bill has a face value of one billion dollars," he said.

According to highly-placed sources in the income tax department, the confirmation of the genuineness of the international bills of exchange issued by a Brazil exchange would be received within end of this week. "We will initiate further investigations only after getting this confirmation," an IT officer said.