The sources said CBI is also expecting to get complete copies of transcripts of phone conversations of middlemen, which were intercepted by Italian agencies, during the next hearing of the case which is scheduled on September 17 in Milan.
Without revealing contents of the fresh set of documents, the sources said the agency will study them and see how they would buttress agency's case.
The sources said a set of over 40,000 documents related to contours of money trail has already been received by CBI from the Italian court after the Defence Ministry became a party in the ongoing case in the European country.
CBI, which carried out probe in India, had named 13 individuals, including Tyagi and European nationals Carlo Gerosa, Christian Michel and Guido Haschke, in the FIR as accused, in connection with the bribery case.
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