An internal White House review has determined that none of its staff members were involved in the Colombia prostitution scandal that has engulfed 23 members of the Secret Service and U.S. military, a spokesman said Monday.

Press secretary Jay Carney said at his daily briefing that the White House counsel’s office has completed a review of all personnel assigned to the advance team for President Obama’s trip to Cartagena for an international summit two weeks ago.

That inquiry found no evidence that any of the political staff members on the trip engaged in personal misconduct, Carney said.

A total of 12 Secret Service employees and 11 members of the military have been implicated in the scandal, which includes allegations of heavy drinking, visits to strip clubs and payments to prostitutes before Obama’s arrival for the Summit of the Americas.

“There was no indication that any member of the White House advance team engaged in any improper conduct or behavior,” Carney said. He added that the review was not prompted by any allegations against White House personnel but rather out of “an abundance of caution.”

Sen. Charles E. Grassley (R-Iowa) asked the White House on Friday to determine whether any of its staffers were involved in the scandal. Monday, he asked for the full results of the White House investigation, including why the counsel’s office conducted the probe so quickly, how many White House advance staff members were in Colombia prior to Obama’s arrival and how many had overnight guests while there.

The advance staff for a presidential trip abroad usually includes hundreds of personnel from the White House, Secret Service, military, State Department and other agencies who are sent as much as two weeks in advance of the president’s arrival.

The Secret Service has dismissed six agents and officers involved in the incident, and five more men are on administrative leave. Their top-secret security clearances have been suspended.

Defense Secretary Leon E. Panetta said Monday that the military has suspended the security clearances of the 11 service members under investigation.

“Frankly, my biggest concern is the issue of security and what could possibly have been jeopardized by virtue of this kind of behavior,” Panetta told reporters. “I’m hoping that our investigators will be able to give us a full report on that.”