A federal watchdog told lawmakers Friday that six women who met with U.S. Secret Service employees in Colombia in April were paid for sex and that other Defense Department and White House staff might also have been involved.

People walk past the Hotel El Caribe in Cartagena, Colombia, on April 19, 2012, where U.S. Secret Service personnel met with prostitutes. (Pedro Mendoza/AP)

In a letter to House and Senate committees, Edwards said that 13 agency staffers “had personal encounters” with women at two Cartagena hotels and a private residence after meeting them at nightclubs in mid-April. Three of the women left without asking for money, five asked for money and were paid, four were refused payment and one woman was paid only after she summoned a Colombian police officer and was later paid by another Secret Service employee, according to investigators.

The dispute that unfolded in the early hours of April 12 exposed the misconduct to local authorities and set off one of the most embarrassing episodes in Secret Service history — just hours before President Obama arrived in Cartagena for the Summit of the Americas.

Eight Secret Service employees, including two senior supervisors, eventually lost their jobs; three were later cleared of serious misconduct; and at least two are fighting to be reinstated.

Seven Army soldiers and two Marines were also implicated in the scandal and received administrative punishments. Three of those personnel requested courts martial.

Allaying one of the primary concerns of lawmakers, Edwards said that he found no evidence that the misconduct “compromised the safety and security of the president or any sensitive information.”

But a hotel registry reviewed by investigators suggested that two other U.S. government employees — working for the Defense Department and White House Communication Agency — also might have met with foreign nationals, Edwards said. Investigators did not pursue the individuals because the Homeland Security inspector general lacks the authority to investigate non-DHS personnel.

In late April, White House Press Secretary Jay Carney said that a White House counsel internal investigation had found no misconduct by White House staffers or the advance team.

But Sen. Susan Collins (R-Maine), one of several lawmakers who requested the probe, said the inconclusiveness surrounding possible White House involvement still troubles her.

“The White House explicitly denied any involvement after its own investigation, and now the IG is questioning that account,” Collins said Friday. “This raises concerns about the credibility of the White House investigation.”

Edwards said his investigation included interviews with 251 Secret Service employees and a review of travel records, hotel registries and U.S. Embassy cables. He launched the probe at the request of lawmakers in late May.

Secret Service spokesman Ed Donovan said the agency had no initial comment on the investigation.

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