The director of the U.S. Secret Service publicly apologized for the first time Wednesday for a prostitution scandal that has rocked his agency as lawmakers revealed fresh allegations of misconduct including reports of non-consensual sex and soliciting prostitutes.

“I am deeply disappointed, and I apologize for the misconduct of these employees and the distraction that it has caused,” Mark Sullivan told senators Wednesday. “The men and women of the U.S. Secret Service are committed to continuing to uphold the standards that the president, the Congress and the American people expect and deserve.”

Sullivan said the employees involved “did some really dumb things” and told lawmakers that their behavior “is not representative of these values or the high ethical standards we demand.”

The director testified before the Senate Homeland Security and Governmental Affairs Committee as the parent agency of the Secret Service continues to investigate how Sullivan and his colleagues handled news that numerous agents had hired prostitutes while in Colombia last month, specifically looking into whether the probe was rushed or if the move to oust most of the men was proper.

Sullivan, who has enjoyed strong congressional support in the weeks since the scandal, faced increasingly skeptical lawmakers Wednesday.

Committee Chairman Joseph I. Lieberman (I-Conn.) said a preliminary review by his office of Secret Service disciplinary records over the past five years has found 64 allegations of complaints involving sexual misconduct.

One case involved allegations of non-consensual sex and most of the allegations involved sending sexually explicit e-mails or sexually explicit material on government computers. There were also 30 alcohol-related cases, most related to driving while under the influence, Lieberman said.

Sullivan told Lieberman at the hearing that the allegation of non-consensual sex was brought by someone outside the agency, but that law enforcement officials declined to press charges after investigating the matter. He also confirmed that an on-duty agency employee in 2008 was caught in an underage prostitution sting and was dismissed a month later.

But Sullivan strongly disputed reports in Wednesday's Washington Post that detailed what happens when large numbers of agents and officers arrive in an overseas city. Tolerance for sexual misconduct and heavy partying and drinking is part of a culture some employees call the “Secret Circus.”

“The notion that this kind of behavior is condoned or authorized is just absurd,” Sullivan said, noting that supervisors had never told him — and he had never told subordinates — that such misconduct is permitted.

Lieberman and his colleagues said they now believe that the behavior committed in Colombia is much more widespread than initially believed.

“It is hard for many people, including me I will admit, to believe that on one night in April 2012, in Cartagena, Colombia, 12 Secret Service agents — there to protect the president — suddenly and spontaneously did something they or other agents had never done before,” Lieberman said. “That is to say, gone in groups of two, three, or four to four different nightclubs or strip clubs and drink to excess and bring foreign national women back to their hotel rooms.”

Sen. Susan Collins (R-Maine), the committee’s ranking Republican, said that the employees involved in the scandal engaged in “morally repugnant” behavior.

“This misconduct was almost certainly not an isolated incident,” she added, noting later that the involvement of two married supervisors with more than two decades of experience, “surely sends a message to the rank and file that this kind of activity is tolerated on the road.”

Homeland Security Acting Inspector General Charles K. Edwards told the committee that his office on Wednesday plans to interview one agent who was implicated in the scandal, the first of several such interviews. Edwards appeared alongside Sullivan at the hearing and both shared details of the unfolding investigation.

Investigators with Edwards’s office have told individuals it has contacted that the review is in its preliminary stages, but that they are examining allegations that the service rushed to judgment and handled its questioning of the men in the prostitution scandal differently than in other alleged misconduct probes.

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Edwards told lawmakers that he was first briefed on the situation April 13, the day that personnel implicated in the scandal were sent home from Colombia. Sullivan and Edwards met in person twice, May 1 and May 4, and Edwards said Sullivan “has repeatedly stated to me his commitment to conduct a complete and thorough investigation. His actions so far have demonstrated that commitment.”

Edwards said his office will review notes from interviews with nearly 200 Secret Service employees who were in Colombia and 25 employees at the hotels in Colombia. He also plans to review how many and what types of polygraph tests were conducted of agency personnel.

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Staff writer David Nakamura contributed to this report.

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