3 US agents sacked over sex scandal.

Three members of the US Secret Service are leaving the agency following the prostitution scandal in Colombia, BBC reported.

Assistant Director Paul Morrissey said one supervisor was sacked, one retired and a more junior employee resigned.

Senior US officials said 20 women were found at the hotel in Cartagena, Colombia, before President Obama went to the Summit of Americas last weekend.

Lie detector tests are being used on the accused as investigations into the scandal continue.

Internal investigators have interviewed witnesses in Cartagena, where a group of agents and military personnel allegedly spent the night with prostitutes at a hotel being used by the American delegation.

Up to 12 members of the US military are also under investigation.