Oregon Public Broadcasting

Portland Mayor Sam Adams is responding the revelations that he had a sexual relationship with an 18-year-old former intern. April Baer reports.

Adams has scheduled an afternoon news conference to elaborate on Monday's written public apology.

Prodded by an investigative story in the Willamette Week newspaper, he's confessed to having sex with Beau Breedlove, who was working as a legislative intern in 2005.

At the time, Adams was a City Commissioner -- he's since been elected mayor. During the mayoral campaign, a political rival raised questions about the relationship.

Adams, who is gay, insisted he had merely mentored a young man coming to terms with adulthood and his sexuality -- a story that Breedlove confirmed to reporters.

Now Adams admits they did have sex, but that it didn't happen until after Breedlove turned eighteen.

Adams goes on to say in the written apology that he  "was afraid that people would believe, 'untrue rumors'" and that he asked Breedlove to lie for him. Adams says he should have been truthful from the beginning.

The admission has shocked a city that hadn't made much of Adam's personal life during the mayoral campaign. In fact, many were proud of having elected an openly gay mayor.