Two more US Secret Service agents have resigned in the wake of the Colombia sex scandal, the agency has confirmed.
In addition, two other agents will face administrative action after being cleared of serious misconduct, and one has had security clearance revoked.
The moves follow the resignation of six others found to be involved in a night with alleged prostitutes while working in Colombia for a pan-American summit.
President Barack Obama earlier described the agents as "knuckleheads".
Speaking at a recording of an NBC chat show, Late Night with Jimmy Fallon, Mr Obama said the vast majority of Secret Service agents performed their duties with no hint of controversy.
"These guys are incredible. They protect me. They protect Michelle. They protect the girls. They protect our officials all around the world," Mr Obama said.
"A couple of knuckleheads shouldn't detract from what they do. What these guys were thinking, I don't know. That's why they're not there any more."
'Will not hesitate'
In a statement, the US Secret Service said the latest measures meant that all 12 of the agents involved in the night out in Cartagena, Colombia, had now been disciplined.
"At this point, all 12 have either been cleared of serious misconduct, resigned, retired, been notified of personnel actions to permanently revoke their security clearances, or have been proposed for permanent removal for cause," the agency said.
"The Secret Service is committed to conducting a full, thorough and fair investigation in this matter, and will not hesitate to take appropriate action should any additional information come to light."
As well as the Secret Service men, who were in Colombia as part of an advance team preparing for Mr Obama's visit to the Summit of the Americas, 12 member of the US military are also under investigation.
The White House has probed the actions of its own team in Cartagena and concluded that its own staff were not involved in the night of debauchery.
Twenty women believed to be prostitutes were discovered with American agents or troops at the beachfront Hotel Caribe after one of the men allegedly refused to pay a previously agreed price for sex, sparking a row.