NBC News has learned that more Secret Service members are under investigation for misconduct in Colombia just before President Obama's summit trip.
As many as 20 agents and uniformed officers on the advance team and five members of the military are now being questioned about wild partying, drinking and prostitutes.
Members of Congress are demanding answers, and so is the president, whose summit agenda was overshadowed by the reports of the Secret Service shenanigans.
The agents involved were not part of the elite Presidential Protective Division, but some were reportedly part of what's called the Counter-Assault Team.
Five members of the military were also caught up in the scandal.
"We're embarrassed about this - though don't know exactly what this is yet," Joint Chiefs of Staff Chairman General Martin Dempsey said Monday.
While the Secret Service is promising a full investigation, the agency itself is facing scrutiny again.
Back in 2009 the Secret Service was under fire after reality TV wannabes Michaele and Tareq Salahi crashed a White House state dinner.
Experts say this is different.
"There's no question this is the biggest scandal in the history of the Secret Service, and these agents could have been blackmailed by these prostitutes to let a terrorist in," says author Ronald Kessler.
"They're out there and representing a lot more than the Secret Service. They're representing America," adds former Secret Service agent Dan Emmett.
As members of Congress discuss the possibility of hearings they're looking at this incident as part of a bigger problem with agency management.