Washington —- A senior U.S. Secret Service inspector admitted Wednesday that she destroyed evidence sought in a long-standing lawsuit alleging that the agency routinely discriminates against African-American agents, including those in its Atlanta office.

A team of assistant U.S. attorneys representing the Secret Service told U.S. Magistrate Judge Deborah A. Robinson that they did not know until the inspector's admission in a court hearing Wednesday that she had placed the documents in a "burn bag" for destruction just two days before her first scheduled testimony in the case Feb. 1.

Robinson told the lawyers that she was "shocked" that a Secret Service agent would destroy documents. The agency's own counsel had ordered employees to retain all documents relevant to the case.

Inspector Carrie Hunnicutt testified in Wednesday's hearing that she had questioned more than 150 senior service officials in response to an order from Robinson for the service to find and hand over all paper documents related to the promotion of black agents in the eight-year-old civil suit.

Nearly 60 African-Americans have alleged in sworn statements that they faced discrimination when they sought promotions. The lawsuit alleges they were passed over in favor of white agents who scored lower on promotional exams and forced to endure co-workers' use of racial slurs and other slights.

Reginald G. Moore, an Atlanta native, is lead plaintiff in the case.

Hunnicutt testified that she destroyed surveys she had collected from about 50 high-ranking officials; a statistical report concerning promotions; and fax sheets and documents that showed who was contacted during the service's search for documents in the case. Under questioning by Assistant U.S. Attorney Michelle Johnson, she said she destroyed the documents because she wanted the most accurate ones to be sent to court.

Hunnicutt said she noticed that some of the surveys were misnumbered, so she transferred the correct information to newly numbered surveys.

E. Desmond Hogan, a lawyer for the plaintiffs, argued that by destroying the original documents, Hunnicutt left the court with no way to independently verify her work as accurate.

Wednesday's hearing was the seventh held by Robinson to determine whether to sanction the Secret Service again for failing to produce credible testimony and evidence in the lawsuit. Robinson has already sanctioned the agency three times. All three sanctions are on appeal. Legal experts say that is a highly unusual number, especially against a government entity.

Assistant U.S. Attorney Marina Utgoff Braswell told Robinson that she and the rest of the legal team did not learn about the destruction until Hunnicutt testified Wednesday.

"We are all learning for the first time what happened here," Braswell said.