The team, headed by a Deputy Inspector General-rank officer, have started the process of going through the tapes and its transcripts running into 49 volumes last week as per the directions of Supreme Court in February this year, official sources said.

A six-member CBI and Income Tax team has began its work of examining over 5800 tapes of tapped conversation of corporate lobbyist Niira Radia with politicians, corporate honchos and others.

The team, headed by a Deputy Inspector General-rank officer, have started the process of going through the tapes and its transcripts running into 49 volumes last week as per the directions of Supreme Court in February this year, official sources said here.

An Apex court bench comprising justices G S Singhvi and S J Mukhopadhaya, while directing formation of the team on February 22, had given four months for it to submit its report.

The team would be scrutinising the tapes to ascertain if there were any elements of "criminality" in them. It would be limited to those conversations which pertain to criminal element and relating to interest of justice.

Few tapes, which found its way to media houses, triggered a political storm as some of the conversations showed the nature of corporate lobbying and its purported impact on politics.

The income tax department has placed transcripts of 5,800 tapped telephone conversations in sealed envelopes. They were recorded as part of surveillance of Radia's phone on a complaint to Finance Minister on November 16, 2007 alleging that within a span of nine years she had built up a business empire worth over Rs 300 crore.

The IT department had recorded 180 days of Radia's conversations--first from August 20, 2008 onwards for 60 days and then from October 19 for another 60 days.

Later, on May 11, 2009, her phone was again put on surveillance for another 60 days following a fresh order given on May 8. (PTI)