New York (CNN) A senior Treasury Department official pleaded not guilty in Manhattan federal court Wednesday to charges that she disclosed sensitive financial transaction reports pertaining to multiple entities tied to President Donald Trump and Russia.

The official, Natalie Mayflower Sours Edwards, allegedly leaked the documents, known as Suspicious Activity Reports, to a reporter whom CNN has previously identified as working for BuzzFeed News.

Prosecutors indicated that a second official could be in legal jeopardy as well, disclosing in court papers that Edwards had discussed with the reporter another employee at the Treasury Department's Financial Crimes Enforcement Network, known as "FinCEN," for whom she used the code name "Enigma."

Edwards told the reporter in a message sent on an encrypted application that "Enigma" had a "wealth of information" and was "willing to verify any information you have and provide additional details as warranted," according to court filings. The filings didn't identify the official.

In response to a question from US District Judge Gregory Woods about the possibility of a superseding indictment or additional charges, Assistant US Attorney Kimberly Ravener left open the potential for an expansion of the case. "Yes, that is possible," she said. "The investigation is ongoing."

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