Revealed! Meet The Mystery Woman Alex Pall Cheated On His Girlfriend With

Chainsmokers' Alex Pall was caught on camera cheating on his girlfriend of four years. Now, RadarOnline.com can exclusively reveal who the mystery woman is!

In January, then girlfriend Tori Woodword blasted Pall after she got her hands on a surveillance video taken inside his apartment building. The tape shows Pall, 32, all over the girl, who RadarOnline.com has identified as 23-year-old model Katelyn Byrd!

But it wasn't just a one-night fling, as the two were spotted together arm-in-arm Thursday night, at a Dior party apparently showing some extreme PDA. Looks like Pall has already moved on from his ex in the blink of an eye!

 According to an insider at the party, they were "full on together" up at the DJ booth.

"He was all over her — hugging and kissing her and holding her hand the whole night," the insider said. "They were just like all over each other."

"They have been talking for a long time and they are always out together," the insider added.

As RadarOnline.com previously reported, upon Woodward's discovery that her boyfriend was a slimy cheat, the NYU grad hit back and slammed the singer on social media.

"They’ll look you in the eyes and tell you they love you. Then destroy you without a second thought,” Woodward, 26 wrote in an Instagram post. "Men are trash. Don’t ever forget it.”

RadarOnline.com has reached out to Byrd for comment.

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