All legal remedies

Justin Bieber is vigorously denying the claims made by a 20-year-old California woman who says in a lawsuit that the 17-year-old singer is the father of her newborn baby.

"While we haven't yet seen the lawsuit, it's sad that someone would fabricate malicious, defamatory and demonstrably false claims," Bieber's publicist said in a statement released on Tuesday. "We will vigorously pursue all available legal remedies to defend and protect Justin against these allegations."

Radar Onlinereports that Mariah Yeater claims she had unprotected sex with Bieber a year ago in a backstage area at one of the singer's concerts and that her three-month-old baby is his. According to an upcoming issue of Star magazine, "in a hand-signed affidavit, sworn under the penalty of perjury, Yeater told a California court that Bieber propositioned her on October 25 of last year, when she was 19. The pair had a sexual tryst after his concert and backstage at L.A.'s Staples Center, it's alleged in court papers."

The affidavit requests that the court compel Bieber to undergo a paternity test to prove whether the child, named Tristan, is his and then to provide "reasonable child support, effective immediately."