An undisclosed number of Secret Service agents with President Barack Obama at an international summit in Colombia have been relieved of their assignments and face an investigation over alleged misconduct, a spokesman for the Secret Service said late Friday.

The Associated Press, citing an anonymous tip, reported that the allegations involved prostitutes in Cartagena, the city hosting the gathering. The AP also said 12 agents were involved. The Washington Post cited the president of the Federal Law Enforcement Officers Association, Jon Adler, as saying that the allegations were tied to at least one agent being involved with prostitutes in Cartagena.

Secret Service spokesman Edwin Donovan declined to confirm that the conduct involved prostitutes.

"There have been allegations of misconduct made against Secret Service personnel in Cartagena, Colombia prior to the President's trip. Because of this, those personnel are being relieved of their assignments, returned to their place of duty, and are being replaced by other Secret Service personnel. The Secret Service takes all allegations of misconduct seriously. This entire matter has been turned over to our Office of Professional Responsibility, which serves as the agency's internal affairs component," Donovan said in a statement sent to Yahoo News by email.

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