Updated at 11:45a.m.ET:
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Homeland Security Secretary Janet Napolitano walks into a Senate Judiciary Committee hearing on April 25, 2012 in Washington, DC.
There was no risk to President Barack Obama as a result of a prostitution scandal at a Colombia hotel that involved a dozen Secret Service officers, Homeland Security Secretary Janet Napolitano told a Senate panel Wednesday.
Napolitano, who was facing questions from the Senate Judiciary Committee for the first time since the scandal erupted earlier this month, testified that the alleged behavior by Secret Service employees is "inexcusable" and a "thorough and full investigation is under way." She said the officers' behavior "was not part of the Secret Service way of doing business."
"All 12...have either faced personnel action or been cleared of serious misconduct," Napolitano said. "We will not allow the actions of a few to tarnish the proud legacy of the Secret Service."
Napolitano also said part of the investigation will include a review of training to see "what if anything needs to be tightened up."
When asked by committee Chairman Sen. Patrick Leahy, D-Vt., if Secret Service officers are specifically training on issues related to having intimate relationships with foreign nationals, she said the training is "focused on professionalism, on conduct consistent of the highest moral standards."
Napolitano also testified that the Secret Service Office of Professional Responsibility, which is investigating the incident in Cartagena, Colombia, had not received any similar complaints of misconduct in the last 2 ½ years.
The Homeland Security inspector general is also supervising the investigation and "the investigatory resources of the Secret Service," she said, adding that she expect the inspector general to do a complete investigation.
Leahy said before the hearing that he wanted to know how thorough the investigation into the misconduct has been and whether such behavior by Secret Service officers has been tolerated in the past.
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"I think that's a very legitimate question. And I've raised it twice with the director of the Secret Service. We'll raise it again," Leahy told NBC's "Today Show."
The Secret Service announced late Tuesday that all 12 implicated officers had been dealt with: eight forced out, one stripped of his security clearance and three cleared of wrongdoing, all within two weeks of the night in question.
The scandal erupted after a fight over payment between a Colombian prostitute and a Secret Service employee spilled into the hallway of the Hotel Caribe ahead of President Barack Obama's arrival at the Summit of the Americas in Cartagena. A dozen military personnel have also been implicated, and Defense Secretary Leon Panetta said they have had their security clearances suspended.
Obama said Tuesday the employees at the center of the scandal were not representative of the agency that protects his family in the glare of public life. "These guys are incredible. They protect me. They protect Michelle. They protect the girls. They protect our officials all around the world," the president said on NBC's "Late Night With Jimmy Fallon."
"A couple of knuckleheads shouldn't detract from what they do," Obama added. "What these guys were thinking, I don't know. That's why they're not there anymore."
Lawmakers across Congress say they are concerned about the security risk posed by the proximity the prostitutes — as many as 20, all foreign nationals — had to personnel with sensitive information on the president's plans.
"No one wants to see the president's security compromised or America embarrassed," Leahy said.
Napolitano said that there was no risk to the president. Questions about the culture of the agency, she said, are still being investigated but she was not aware of this being a wider problem.
"This behavior was not part of the Secret Service way of doing business," Napolitano testified. "We are going to make sure that standards and training, if they need to be tightened up they are tightened."
Elsewhere on Capitol Hill, House Speaker John Boehner said the scandal is an embarrassment to the agency and the United States, but stopped short of calling for an independent investigation.
"What I'm looking for are the facts. I don't want to just jump out there and make noise just to be making noise," Boehner told reporters. "Let's get to the bottom of this."
The Colombia scandal has been widely denounced by official Washington, but it's a delicate political matter in an election year with the presidency and congressional majorities at stake. All sides have praised Secret Service Director Mark Sullivan's swift action and thorough investigation, in part because he's spent significant time keeping key lawmakers in the loop. Pentagon officials, too, are investigating and are expected to brief Senate Armed Services Committee Chairman Carl Levin and ranking Republican John McCain on Wednesday.
In a similar but unrelated incident, Panetta said Tuesday that three Marines on a U.S. Embassy security team and one embassy staff member were punished for allegedly pushing a prostitute out of a car in Brasilia, Brazil, last year after a dispute over payment. Panetta, speaking in Brasilia, said he had "no tolerance for that kind of conduct."
The military investigation into the Cartagena incident is continuing.
Another Senate panel is looking for a pattern of misconduct. Sen. Joe Lieberman, chairman of the Homeland Security and Governmental Affairs Committee, told reporters on Tuesday that he'll hold hearings on the service's culture and whether clear rules exist on how employees should behave when they are off duty but on assignment.
"I want to ask questions about whether there is any other evidence of misconduct by Secret Service agents in the last five or 10 years," Lieberman said. "If so, what was done about it, could something have been done to have prevented what happened in Cartagena? And now that it has happened, what do they intend to do?"