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Three Secret Service agents out in prostitution scandal

Three Secret Service employees will leave the agency in the wake of a Colombian prostitution scandal which took place when the agents were protecting President Obama during a visit to South America. NBC's Mark Potter reports.

Updated at 7:03 p.m. ET: Three Secret Service agents implicated in the scandal involving the procurement of women during President Barack Obama's trip to Colombia are leaving the agency, a spokesman said Wednesday.

In a statement, the spokesman, Paul Morrissey, said a supervisory employee was allowed to retire, a second supervisory employee was listed for "removal for cause" and a non-supervisory employee had resigned.

Eight other agency employees remain on administrative leave without their security clearances, Morrissey said.

The statement confirmed a report earlier Wednesday by NBC News that the implicated agents were "offered" the opportunity to submit to polygraph tests. A U.S. official told NBC News that some of them had agreed.

New details of the scandal emerged after a round of congressional briefings Wednesday.

Eleven women were involved with 11 Secret Service personnel, a Senate source told NBC News. Investigators are looking into reports of drug use but haven't found any evidence yet, the source said.

None of the 11 men had guns, radios, equipment or schedules in their rooms, the source said, clarifying questions raised on Capitol Hill about whether operations or presidential security may have been compromised.

As a result of the scandal, the agency is undertaking a review of its policies regulating contact with foreign nationals, the source said.

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"We demand that all of our employees adhere to the highest professional and ethical standards and are committed to a full review of this matter," the agency's statement said.

Three of the 11 Secret Service agents implicated in the Colombia prostitution scandal are leaving their posts, and eight more are on administrative leave. NBC's Kristen Welker reports.

Secret Service Director Mark Sullivan has told lawmakers that the 11 agents and 10 U.S. military personnel also implicated in the scandal are giving investigators conflicting stories, making it difficult to pin down the truth, according to several lawmakers who spoke to NBC News on Wednesday.

The Colombian government is separately investigating whether underage girls were part of the arrangements, but Sen. Charles Grassley of Iowa, the top Republican on the Judiciary Committee, said Sullivan believes the youngest woman involved was about 20 or 21 years old.

Grassley said Judiciary Committee staff members would meet with agency representatives later this week for a more complete briefing. He said the committee would conduct its own investigation only if members concluded that the Secret Service inquiry "was not doing the job."

Regardless, Grassley said, "I think you'll find their heads are going to roll." He added that he was worried that there could be a culture of misbehavior at the Secret Service, a concern that was echoed by Sen. Susan Collins, R-Maine, who has also been briefed on the case.

Collins told NBC News that her "instinct" is that this wasn't an isolated incident. She said that she pressed Sullivan and that he had told her the agency was "scrubbing the files" for possible previous incidents.

The Defense Department is separately investigating the 10 military members who have been implicated. Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, said Tuesday that "we let the boss down" in Colombia.

Defense Secretary Leon Panetta is expected to brief leaders of the Senate Armed Services Committee in the next couple of days, Sen. John McCain, R-Ariz., told NBC News on Wednesday.

Kristen Welker of NBC News and M. Alex Johnson of msnbc.com contributed to this report by Michael Isikoff and Libby Leist of NBC News.

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