Seattle-based Investigative Reporter Chris Halsne (KIROTV- CBS- COX MEDIA GROUP) just returned from El Salvador, where he interviewed a U.S. government subcontractor who worked extensively with the Secret Service advance team (snipers, K-9 and explosives sweeps) in San Salvador prior to President Obama’s trip there in March of 2011. 
 
 The eyewitness says he joined about a dozen Secret Service agents and a few U.S. military specialists at a strip club in San Salvador a few days before President Obama and his family arrived in El Salvador to meet with its new president, Mauricio Funes. 
 
 This source witnessed the majority of the men drink heavily ("wasted," "heavily intoxicated") at the strip club. He says most of the Secret Service "advance-team" members also paid extra for access to the VIP section of the club where they were provided a number of sexual favors in return for their cash. Although our source says he told the agents it was a "really bad idea" to take the strippers back to their hotel rooms, several agents bragged that they "did this all the time" and "not to worry about it." Our source says at least two agents had escorts check into their rooms. It is unclear whether the escorts who returned to the hotels were some of the strippers from the same club. 
 
 These alleged incidents in El Salvador occurred a full year prior to recent revelations that secret service agents used prostitutes in Cartagena, Colombia, on a presidential trip this month. 
 
 To further confirm information provided about behaviors in El Salvador that reportedly occurred in March of 2011, Halsne interviewed the owner of the San Salvador strip club in which the subcontractor said they visited. The strip club’s owner confirmed a large number of U.S. secret service agents (and some military escorts) “descended on his club” that week prior to President Obama’s visit. He claims agents were there at least three nights in a row. "No surprise to me." The owner told Halsne his club routinely takes care of high-ranking employees of the U.S. embassy in San Salvador as well as visiting FBI and DEA agents. The owner says his reputation for "security" and "privacy" makes him a popular strip club owner with "those who want to be discreet." He told Halsne during a lengthy interview, he doesn’t allow prostitution inside the club and that all his "girls" are at least 18-years-old. He says the girls can do what they want after work, but he discourages them from making contact with customers at other locations. 
 
 This investigation is still fast-developing. Halsne has names of some of the agents allegedly involved in the partying and has viewed records which add credibility to the subcontractor’s eyewitness testimony. KIRO-TV is currently writing and editing-together a series of television stories for air beginning at 5 p.m. on Thursday, April 26. ||||| U.S. Secret Service director Mark Sullivan has been briefing members of Congress about the allegations that the Secret Service and military personnel brought prostitutes back to their hotel in Colombia last week. NBC's Kristen Welker reports. 
 
 The Colombian prostitute who triggered the scandal that has rocked the Secret Service got angry with two agents who refused to pay her full price for servicing the two of them, leading to a financial dispute over between $40 and $60, according to a government source who has been briefed on the investigation. 
 
 Two agents from the service's elite Counter Assault Team, in Cartagena, Colombia, in advance of President Barack Obama's arrival for the Summit of the Americas over the weekend, had procured the women's services at a local strip club called the Pley Club on the evening of April 11. All the Secret Service agents and officers implicated in the scandal are believed to have gone to the club that evening and brought back women, a U.S. official told NBC News. 
 
 The controversy arose after one of the women went back to a hotel room with two agents. The woman wanted to be paid for serving both agents, the source who has been briefed on the probe told NBC News. Instead, the agents would only agree to split her price, prompting the woman to complain to local police who were stationed in the lobby of the Hotel Caribe, the source said. 
 
 The police then went up to the agents' room and began banging on the door, which the agents at first refused to open, the source said. There are conflicting reports over how the payment dispute was resolved. But two government sources told NBC News the police contacted the U.S. Embassy over the dispute and Embassy officials then arrived at the scene. 
 
 All those with booked rooms at the hotel had to pay a fee of $25 for bringing any guests to their rooms -- and the guests were required to leave some form of identification at the front desk. A quick scan of the hotel register by a U.S. Embassy official established that 11 Secret Service agents had brought back women to their rooms that evening. When Embassy officials notified Secret Service Director Mark Sullivan, he immediately ordered all the agents to fly home, the sources said. 
 
 MSNBC's Thomas Roberts speaks with NBC National Investigative Correspondent Michael Isikoff and former Secret Service agent and current Senate candidate Dan Bongino about the fallout from the Secret Service prostitution scandal. 
 
 The Secret Service members -- including agents and uniformed officers -- were stripped of their security clearances on Monday. 
 
 Included in that group were two high-level Secret Service supervisors, three counter assault officers whose job is to repel attacks and three sniper-team members, who take to rooftops to secure areas where the president might visit, NBC News reported. 
 
 U.S. officials have described the agents' conduct as a potential security breach especially because all the agents involved had access to the president's day-by-day, minute-by-minute schedule. But one official familiar with the security arrangements said that there were no specific security threats during the president's trip. Although agents upon arrival were briefed about current activities by leftist FARC guerrillas and local drug cartels, they were told neither had made any specific threats to the president. 
 
 The only specific security concern mentioned was that agents and officers were told to bar a left-wing journalist from events at the summit and were given a flier with the journalist's photograph to keep him out, the law enforcement source said. 
 
 The Secret Service sent agents to Colombia to interview the prostitutes who hooked up with the Americans to figure out if the women are under age, involved with terrorism or trafficking in illegal drugs, a lawmaker told NBC News' Luke Russert on Tuesday. 
 
 “They have all their IDs and are conducting an extensive background check to make sure they aren't affiliated with any narcotrafficking or terrorist group or that they could be minors,” Homeland Security chairman Rep. Peter King told Russert. “So far there is no security breach." 
 
 Former Secret Service agent Dan Bongino, who worked in the presidential protection division, shares his view of the scandal involving at least 11 Secret Service personnel and more than 5 military personnel. 
 
 King, who was briefed on the Colombia investigation by Sullivan, confirmed that there were 11 agents and 11 women. 
 
 "The investigation could take a while simply because of the amount of women involved,” King said. “Some are saying they were prostitutes and others say they weren't." 
 
 U.S. military officials told NBC News on Tuesday that 10 American servicemen also were under investigation. According to the officials that includes five Army soldiers, two Navy sailors, two Marines and one Air Force airman. 
 
 One military official says it appears that at least two of the service members were found with prostitutes in their hotel rooms, the same Hotel Caribe where the Secret Service detail stayed. 
 
 It's not clear whether any of the military members were in any way connected to the allegations involving members of the Secret Service at a Cartagena strip club. 
 
 It's also not yet clear whether any of the 10 will face criminal charges. 
 
 House and Senate lawmakers are also looking into the allegations. King told The Associated Press that his committee is devoting four investigators to the probe. 
 
 Meanwhile, one former Secret Service agent, Dan Bongino who is a Republican candidate for Congress in Maryland, told NBC News that in his 12 years at the agency he never saw anything like what is alleged to have taken place in Colombia. 
 
 “I’m not saying it’s never happened, but I never saw it.” Bongino said. He denied there was a culture of partying inside the agency. 
 
 Top US military officer: 'We let the boss down' over prostitute scandal 
 
 A decade ago, however, U.S. News and World Report published an investigative report detailing criminal activity and extreme partying as well as oversight problems. In one reported incident, members of Vice President Dick Cheney’s security detail got into a brawl outside a bar on a trip to the San Diego area. 
 
 New details about the Secret Service personnel alleged to have brought prostitutes to their hotel rooms have emerged, including reports that two of the 11 were supervisors. NBC's Kristen Welker reports. 
 
 As the agency sought to rebuild its image, other high-profile incidents with presidential protection brought more scrutiny. 
 
 In 2008, an Iraqi journalist threw shoes at President George W. Bush during a Baghdad visit. 
 
 And in November 2009 three people crashed a White House state dinner for Indian Prime Minister Manmohan Singh. Michaele and Tareq Salahi and Carlos Allen were able to get past Secret Security agents at the door and enter the party. 
 
 The Salahis even met Obama and had their picture taken with Vice President Joe Biden. In a January 2010 congressional hearing on the matter, the Salahis, who have since divorced, refused to testify, invoking their Fifth Amendment right against self-incrimination. 
 
 The prostitution scandal, however, has brought far more intense focus on the Secret Service and behavior by its agents and officers. 
 
 "This really is the biggest scandal in the history of the Secret Service," Ron Kessler, author of "In the President's Secret Service," told NBC News earlier this week. He said the agency's problems are deeply rooted. 
 
 "There's a culture in the Secret Service that's fostered by the management of just nodding, winking, favoritism," he said. "What the agency needs is an outside director who can come in, clean house, change the standards." 
 
 Michael Isikoff is NBC News' national investigative correspondent; Jim Miklaszewski is NBC News' chief Pentagon correspondent. NBC News Correspondent Luke Russert and msnbc.com reporter Jeff Black also contributed to this report. 
 
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– Looks like there are teeth to the rumors that the Secret Service's Colombian sex adventure wasn't a one-time thing. The Service is investigating reports that its agents were serviced by prostitutes on a trip to El Salvador in March of last year, according to the Hill. A government subcontractor told KIRO-TV that he visited a strip club with about a dozen Secret Service Advance Team members, and that most got "wasted" and paid the strippers for sexual favors in the VIP section. A couple of agents also brought women (possibly the aforementioned strippers, possibly not) back to their hotel rooms. The source says he warned them that it was a "really bad idea" but they replied that they "did this all the time" and "not to worry about it." The club's owner confirmed the story, saying agents showed up at least three nights that week, though he noted that he did not allow prostitution on-premises. He said the visit was "no surprise to me" because his club was popular with "those who want to be discreet."