A New York Times reporter has appeared for the second time before a grand jury investigating the leaking of the identity of a secret CIA agent.
Miller spent 85 days in jail for refusing to testify
Judith Miller is reported to have found notes about previously undisclosed talks with a vice-presidential aide.
The name of CIA agent Valerie Plame was revealed by another journalist in 2003. Her identity was alleged to have been leaked by a White House official.
Ms Plame's husband, an ex-diplomat, had criticised President Bush over Iraq.
Former ambassador Joseph Wilson claims the Bush administration deliberately tried to get back at him by identifying his wife.
The special prosecutor must determine if anyone deliberately revealed Ms Plame's identity to journalists and whether they knew she was a covert agent.
If he finds that this was the case, he could bring criminal charges.
Several White House officials have appeared before the grand jury, including Lewis "Scooter" Libby, an aide to the vice-president, and presidential adviser Karl Rove.
Miller - who never wrote a story about Ms Plame - initially refused to co-operate with the investigation, citing a confidentiality arrangement she had made with her source.
But after she had spent 85 days in jail, Mr Libby waived the pledge and she testified on 30 September about two conversations with him.
Karl Rove is to appear before the grand jury for the fourth time
After that appearance, the New York Times reports, Miller found some notes in the newsroom relating to a third conversation with Mr Libby.
She handed these notes over to the prosecutor, Patrick Fitzgerald, on Tuesday, ahead of her second appearance before the grand jury.
Mr Fitzgerald has said he will also summon Karl Rove to testify for the fourth time before the grand jury, which is not open to the public.
Mr Rove had conversations about Plame with at least two other journalists, but he says he did not name her and did not even know her name at the time.
Mr Libby also says he learnt her name at a later date.
The prosecutor is expected to report on the inquiry by the end of the month.