CBI has recently examined a senior journalist in connection with its probe into tapped conversations of lobbyist Niira Radia.
The sources said the journalist working with a television channel was called in connection with Radia's conversation in which her phone interaction with the lobbyist also surfaced.
The sources said the conversation was allegedly linked to some purported financial transaction.
The agency has said the journalist was only called to confirm some information.
It has also said the journalist has not been named in any of the preliminary enquiries related to the case.
More people who were part of Radia's telephonic conversations will be called for questioning, they said.
A Supreme Court bench headed by Justice G S Singhvi had identified 23 issues which were framed by an apex court-appointed team on the analysis of the tapped conversations of Radia with bureaucrats, politicians, business honchos and journalists.