Justin Bieber: denyng a potential paternity suit. (Donald Traill/AP)

While Justin Bieber spent his Tuesday evening performing on “Dancing With the Stars” to promote his new holiday CD, a tabloid story was breaking online.

That story, to be published Thursday in Star magazine and first reported by Radar Online, says that a 20-year-old woman has filed a paternity suit against Bieber, 17, alleging that the singer fathered her child after a brief backstage tryst at a Bieber concert at L.A.’s Staples Center.

But reps for the singer — deified by impressionable young girls the world over — are adamantly denying the story.

“While we haven’t yet seen the lawsuit, it’s sad that someone would fabricate malicious, defamatory, and demonstrably false claims,” Bieber’s team tells E! Online in a statement. “We will vigorously pursue all available legal remedies to defend and protect Justin against these allegations.”

While the claims may be false, they are notable because they mark the first time that Bieber has been caught up in a scandal. Prior to this moment, the wholesome kid who charmed young girls and their parents in the movie “Never Say Never” hadn’t been involved in anything much more controversial than a water balloon fight and some public kissing with girlfriend Selena Gomez.

Given Team Bieber’s denial of the story, presumably the paternity suit — repotedly filed in a California court on Oct. 31 by a woman identified as Mariah Yeater, who gave birth to a baby boy in July — will not tarnish Bieber’s reputation. But one can assume this is a story that won’t go away immediately.

Bieber acknowledged the situation vaguely by tweeting, “all the rumors...the gossip....Im gonna focus on the positives....the music.”

That message was retweeted by more than 100 people, all of them presumably still Beliebers.