The Pentagon said more US military personnel may be involved in "inappropriate behavior" in Colombia, after the Secret Service sent 11 agents home for allegedly hiring prostitutes at a Cartagena hotel, the Associated Press reported.
Pentagon press secretary George Little said he could not provide a specific number of men involved but it was greater than the five originally cited.
The Defense Department ordered its own probe after determining half a dozen of its employees were staying at the same hotel at the Secret Service. One official told CBS News, "more than 10" members of the military could be involved.
Rep. Darrell Issa of California, the Republican chairman of the House Oversight and Government Reform Committee, said Monday it's not unheard of to have "wheels up parties" at the end of a trip but this was a "pre-wheels up party."
More from GlobalPost: Obama calls for investigation into Secret Service prostitution scandal
"You had drinking and activity that clearly compromised the ring of security," Issa said. "What we're concerned about is that failure today can lead to blackmail" down the line since the agents allegedly brought the prostitute into a secure area.
On Sunday, President Barack Obama said, "I’ll be angry," if the charges prove true and ordered a "thorough and rigorous" investigation into the 11 US Secret Service agents, according to the Washington Post.
Those agents, now on administrative leave by the Secret Service, were working in advance of Obama's visit to Colombia for the Summit of the Americas.
The issue apparently came to light after local police contacted the US Embassy when one of the women complained she wasn't paid for her services, and refused to leave the hotel.