Eleven Secret Service agents sent to Colombia ahead of the president's visit have been accused of misconduct involving prostitution.
While still in Cartagena for the Summit of the Americas, President Obama addressed the allegations.
"These men and women perform extraordinary service on a day-to-day basis, protecting me, my family, and U.S. officials. They do very hard work under very stressful circumstances and almost invariably do an outstanding job.
And so I'm very grateful to the work they do. What happened here in Columbia is being investigated by the director of the Secret Service.
I expect that investigation to be thorough and I expect it to be rigorous. If it turns out that some of the allegations that have been made in the press are confirmed, then of course I'll be angry because my attitude with respect to the Secret Service personnel is no different than what I expect out of my delegation that's sitting here.
We're representing the people of the United States. And when we travel to another country, I expect us to observe the highest standards because we're not just representing ourselves.
We're here on behalf of our people and that means we conduct ourselves with the utmost dignity and probity. And obviously what's been reported doesn't match up with those standards. But again, I think I'll wait until the full investigation is completed before I pass final judgment."
Two U.S. government sources say the agents were relieved of duty and returned home.
PRESIDENT CARTAGENA SUMMIT OF AMERICAS