Obama calls for investigation into Secret Service prostitution scandal

President Barack Obama said Sunday that he wants a thorough and rigorous investigation of the 11 US Secret Service agents who were sent home from Cartagena, Colombia, after the agents allegedly brought prostitutes to their hotel rooms.

The agents were placed on administrative leave April 12 pending an internal investigation, according to a statement by Secret Service spokesman Paul S. Morrissey, Bloomberg Businessweek wrote.

The Washington Post reported if the charges prove true, Obama said, “then, of course, I’ll be angry," and that he expects US personnel to “observe the highest standards” when serving abroad.

More from GlobalPost: Obama's Secret Service in prostitute scandal (VIDEO)

Obama made the comments during a news conference Sunday at the end of the Summit of the Americas. They are his first about the growing scandal.

Meanwhile, the Post said the Defense Department ordered its own inquiry after determining if a half dozen of its employees, who were staying at the same hotel as the Secret Service agents, violated curfew on Wednesday night.

The issue came to light after one of the women complained to Colombian police that she had not been paid. The police reported the matter to the US Embassy.

Representative Darrell Issa of California, the Republican chairman of the House Oversight and Government Reform Committee, told CBS’s “Face the Nation” that there may as many as “20 or more” people involved and that the Secret Service may need to do "some soul searching."