Ruggieri is one of several people from Delaware County who have spoken with the FBI, a source said. At least three of them, excluding Ruggieri, have testified before a federal grand jury in New York, the source said.
"The case is based in Brooklyn, but most of the players are from Philly," said another person involved, who spoke on the condition of anonymity.
No one has been charged with a crime in the case, and federal authorities in Brooklyn, where the investigation is based, have declined to comment.
During a news conference last week, NBA commissioner David Stern said the FBI approached him in late June about "a referee alleged to be gambling on games."
"We are not positive it's games that he worked, although I understand that some of those are games specifically that he worked," Stern said of Donaghy. "I understand that he is accused of, or likely to be accused of, providing information to others for the purpose of allowing them to profit on betting on NBA games."
Donaghy, 40, who graduated from Cardinal O'Hara High School and Villanova, resigned last month after a 13-year career in the NBA.
His lawyer, former federal prosecutor John F. Lauro, said yesterday that "it would be highly irresponsible for counsel to make any statement at this time."
"I expect to make all of my comments to the court and not to the press," Lauro said.
During his news conference, Stern said Donaghy rated in the "top tier of accuracy" in his officiating.
Warren and others involved said Ruggieri was a relatively minor player with a limited view of the case. Nevertheless, the questions FBI agents asked during his interview last month at Warren's law office in Philadelphia provide a glimpse of the investigation.
Among the questions, Warren said, was: Did Donaghy bet on NBA games?
"His answer was he didn't know," Warren said.
FBI agents did not ask whether other NBA referees might be involved, Warren said.
