The head of the Secret Service is calling for an independent review of the agency's investigation into the Colombian sex scandal.
Meanwhile, the agents under investigation are telling different stories about whether they knew the local women were prostitutes.
U.S. lawmakers want to know if the women had access to sensitive information that could have jeopardized the president's security.
The Secret Service agents accused of soliciting prostitutes will be forced to take lie detector tests.
U.S. inspectors are in Colombia interviewing witnesses and collecting hotel surveillance video. Sources say many of the suspected prostitutes have been identified and will be interviewed.
"When you bring a guest into a hotel in Colombia they have to leave their photo ID at the main desk," explained Rep. Peter King, GOP chairman of the Homeland Security Committee.
The New York lawmaker also said some of the agents implicated in the sex scandal are talking but their stories are different.
"Some admit they did the wrong thing," King elaborated. "Others are denying there was any involvement with prostitution, that these were just women they happened to meet."
Sources also say that 10 or more military personnel from every branch of the service are implicated in the scandal.
"We let the boss down because nobody's talking about what went on in Colombia other than this incident," Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, said.
In addition, as many as 21 local women were allegedly involved. Lawmakers say national security was put at risk.
"They could be employees of the local drug cartels," Sen. Susan Collins, R-Maine, said. "They could be spies, planted eavesdropping devices, kidnapped them."
The White House said President Obama still has confidence in the director of the Secret Service. The president is receiving regular updates on the investigation.
"All of the women in America were insulted, were offended by the actions of these individuals," Rep. Sheila Jackson Lee, D-Texas, said.
The Washington Post reported Wednesday that several of the military members allegedly involved in the scandal are members of the Army's Green Berets. The Green Berets are working with Colombia's counterterrorism teams.