LOS ANGELES -- A longtime friend of Lance Armstrong's testified Wednesday before a federal grand jury hearing evidence connected to allegations of doping in professional cycling, people familiar with the case told The Associated Press.

The sources, who spoke on condition on anonymity because the case is ongoing, say Stephanie McIlvain appeared before the panel, which met all day. Her attorney, Thomas Bienert, was also seen outside the area where the grand jury met. He didn't return phone and e-mail messages seeking comment.

McIlvain is important to the case because she was present in the hospital room where Armstrong was being treated for cancer in 1996, when former teammate Frankie Andreu and his wife, Betsy, claim the cyclist told doctors he had used performance-enhancing drugs.

Armstrong vehemently denies that he cheated -- or that he made such a statement -- and McIlvain has previously testified in a civil case that she didn't hear the seven-time Tour de France champion admit to doping in that conversation.

However, in a phone call secretly recorded by Tour winner and Armstrong critic Greg LeMond, McIlvain seemed to take a more ambiguous stance, saying that she heard the hospital conversation and would testify in a lawsuit if subpoenaed. However, she never said exactly what she heard.

Unauthorized versions of the LeMond-McIlvain conversation have long been available on various cycling websites.

McIlvain was a liaison between Armstrong and sunglasses-maker Oakley, one of his sponsors.

Federal prosecutor Doug Miller declined comment after Wednesday's proceedings.

Betsy Andreu said earlier this month she spoke with Food and Drug Administration agent Jeff Novitzky about Armstrong, but declined to give details.

Armstrong became a more important figure in the federal probe this spring after disgraced cyclist Floyd Landis dropped long-standing denials and admitted he used performance-enhancing drugs. In doing so, he accused Armstrong and others of systematic drug use. Landis won the Tour in 2006, but was stripped of his title for doping.