Riggs National Corp.'s board of directors commissioned an internal investigation of the company's business dealings with Augusto Pinochet, including allegations that the banking company helped the former Chilean dictator hide millions of dollars from international prosecutors.

Included in the inquiry will be how Pinochet became a customer of Riggs and what role Riggs's largest shareholder and former chief executive, Joe L. Allbritton, may have played in attracting and handling Pinochet's accounts.

Separately, Riggs officials have decided to place R. Ashley Lee, an executive vice president and Riggs Bank's former chief bank examiner, on paid leave until a Justice Department investigation into whether he violated government ethics rules is resolved, according to sources with knowledge of the matter who spoke only on the condition of anonymity because of the ongoing nature of the investigation.

Lee, who retired as a bank examiner with the federal Office of the Comptroller of the Currency (OCC) in 2002, became a subject of intense scrutiny this summer by congressional investigators and the Treasury Department for his role in a decision about whether to include results of an OCC investigation of Riggs and Pinochet in the Riggs case file. Two other bank examiners have said Lee instructed them to keep the material out of the files a month before he was offered a job as a senior executive with Riggs. Lee testified at a recent Senate hearing that he did not remember giving such an instruction.

Lee could not be reached for comment, and a lawyer representing him said last night that he was unaware of any change in his client's employment status.

The board inquiry was initiated within days of the release of a July 15 Senate report detailing Riggs's extensive dealings with Pinochet, including efforts to create shell companies to help the retired general shield several million dollars from outside scrutiny. According to sources familiar with board members' thinking, but who spoke on condition of anonymity because of ongoing regulatory and criminal investigations, the board's independent directors were taken by surprise by the extent of the alleged wrongdoing in Riggs's handling of the Pinochet accounts as described in the Senate report.

The directors, according to the sources, want to make sure that they know the extent of the relationship and that no more surprises are in store. A key question is whether Allbritton had a personal as well as professional relationship with Pinochet and, if so, how that affected the bank's actions.

The board asked law firm Sullivan & Cromwell LLP, which has been advising board members during Riggs's growing scandal, to oversee the investigation. Both Sullivan & Cromwell and the bank's internal investigators are conducting the inquiry.