AceShowbiz -

"Teen Mom" star Amber Portwood shed her clothes for some racy pictures. The 20-year-old mom, who was arrested for domestic battery last year, is snapped standing sideways, covering her breast with her hand and slightly lifting her leg to hide her modesty. She exposes an enormous tattoo of her two-year-old daughter, Leah, on the right side of her torso.

According to Radar Online which obtained the nude pictures, Amber was at a friend's home when doing those naked poses a few weeks ago. "Amber fancies herself an old-fashioned pin-up girl," a source said. "She just wanted to pose!" And the young mother did it "the way she thought a pin-up would."

But Amber denied it to E! Online, "Radar Online totally lied. That is my room, that is my bed, my mirror...you can tell that's my room and when the show [Teen Mom 3] comes out, everyone will see that it's my room." She added, "Those pics were taken for personal reasons. I didn't send them to anyone. I didn't take them for sexual reasons. This is embarrassing enough. It's just weird. The person who did this is f**ked."

She knew who leaked the pictures, but refused to reveal who the person is because she "wants to surprise them." She noted, "I've never given anything to anybody. I wouldn't do that. I know 100 percent who did it, and I'm going to go after them full force."

When asked whether it's her ex Gary, Amber quickly dismissed the speculation, "No, no, Gary didn't do it. He wasn't around me because of the no contact order when I took those pictures, but there were a bunch of people who were and I'm sure I know who it was."

To MTV, she spilled the beans that the one who stole the photos from her cellphone is someone she trusted. "It makes me sad that anyone would do this, and I'm horrified that something so private is being shared publicly," she stated. "It's been a difficult year and I just want to focus on what's important in my life - my daughter."