WASHINGTON (Reuters) - Two more U.S. Secret Service agents are resigning over a scandal in Colombia involving prostitutes, two government sources told Reuters on Tuesday.

A third agent faced termination proceedings, said one of the sources, who asked not to be named. Six other agents have already left the agency over the alleged misconduct with prostitutes earlier this month in Cartagena, Colombia, before the president arrived for a summit.

(Reporting By Susan Cornwell; Editing by Sandra Maler)