Three more Secret Service agents resign

Three more Secret Service agents have resigned from the agency in the wake of a prostitution scandal in Colombia.

The three chose to resign from the agency, bringing the total number of departures to six.

One more agent has been implicated in the prostitution episode and is now under investigation, brings the total number of agents involved in this incident to 12. The additional agent, who has been placed on administrative leave, had his security clearance temporarily suspended pending the outcome of the investigation.

One of the Secret Service employees implicated in the scandal has been cleared of serious misconduct but will face "appropriate administrative action," said Assistant Director Paul Morrissey.

Five other agents remain on administrative leave with their security clearances suspended for the time being.

Morrissey said the investigation continues and the agency is using all investigative techniques available, including polygraph examinations.

A senior White House official tells The Hill that the President Obama received his first briefing in the Oval Office Friday afternoon from Secret Service Director Mark Sullivan on the investigation.

White House spokesman Jay Carney has reiterated in recent days that Obama has "confidence" in Sullivan.

The U.S. military has also increased the number of service members involved in the incident to 11 from 10.

Obama's trip to Colombia last week was overshadowed by the allegations that the agents drank heavily and hired prostitutes.

Updated at 6:55 p.m.