"Never met the woman," Justin said. "I'd just like to say, basically, that none of the allegations are true. I know that I'm going to be a target, but I'm never going to be a victim," the 17-year-old said.
Mariah, 20, claimed she was taken backstage at his Staples Center concert last year to meet Bieber, and subsequently had sex with him in a bathroom. Yeater, whose son was born three months ago, told Star magazine, "On July 6, 2011, I gave birth to a baby boy. That was exactly 36 weeks and two days after the sexual encounter with Justin Bieber. Based upon the timing as well as the fact there were no other possible men that I had sex with that could be the father of this baby, I believe that Justin Bieber is in fact the father of my baby."
The singer told the hosts of "Today," "It's crazy. Every night after the show I'm gone right from the stage right to the car, so it's crazy that some people want to make such false allegations."
Yeater claimed she initially considered giving the baby up for adoption, but decided against it, according to the NY Post.
Racy photos of the new mom have also surfaced on Daily Mail -- who reported her less-than-squeaky-clean past, which included a battery charge filed against her for slapping ex-boyfriend John Terranova while she was two months pregnant.
TMZ reports that this isn't Mariah's first time accusing someone of being her baby's daddy. She originally accused Terranova of fathering the same baby, according to his grandmother.
Terranova denied getting Yeater pregnant, and the two were involved in a heated argument, in which police were called to the scene. Yeater allegedly broke a car window out of anger. She slapped John in the face three times and was arrested and charged with battery.