The Secret Service prostitution scandal grew after a further investigation on Tuesday revealed that at least 20 women had been in hotel rooms with U.S. agents and military personnel before the summit with Latin American leaders.

According to Secret Service Director Mark Sullivan, 11 Secret Service agents and 10 military personnel are being investigated. Military officials revealed that five Army Special Forces soldiers were part of those personnel in question.

One of the officials said the group includes six members of the Army's Special Forces, two Navy Explosive Ordnance Disposal technicians, two Marine dog handlers and an Air Force airman. The Special Forces soldiers were working with Colombia's counterterrorist teams, the official said in the AP report.

"Some are admitting (the women) were prostitutes, others are saying they're not, they're just women they met at the hotel bar," King said in a telephone interview according to an Associated Press report.

Sullivan said none of the women, who had to surrender their IDs at the hotel, were minors. "But prostitutes or not, to be bringing a foreign national back into a secure zone is a problem," Sullivan said.

Visitors spending the night in  the hotel are required to leave identification at the front desk and leave the hotel by 7 a.m. When one woman failed to do so, it raised a red flag among hotel staff and police, who investigated. They found the woman with the agent in a hotel room and a dispute arose over whether the agent should have paid her.