Justin Bieber and Skrillex are being sued for copyright infringement by an artist who claims they stole the hook on Bieber's Purpose track "Sorry" from one of her songs. Indie artist White Hinterland took to Facebook to explain she is suing because "Sorry" copies the the vocal riff prominently featured in her song "Ring the Bell" and that the writers, producers, and performers of "Sorry" did not obtain a license or permission from her to do so.

Hinterland goes on to claim she approached Bieber and his team after "Sorry" initially dropped and Bieber's team "refused to even acknowledge [her] claim" despite her offering them an opportunity to have a private conversation about the situation.

"I poured my blood, sweat, and tears into writing and producing 'Ring the Bell,' and I am proud of the finished product, which Rolling Stone listed as one of its 'favorite songs, albums, and videos,'” Hinterland wrote on Facebook. "Throughout my career, I have worked very hard to preserve my independence and creative control, thus it came as a shock to hear my work used and exploited without permission."

Ultimately, Hinterland feels she was left with no choice but to file a lawsuit. "Justin Bieber is the world’s biggest artist, and I’m sure that he and his team will launch a full attack against me. But, in the end, I was left with no other option," she wrote. "Sorry" is one of Bieber's biggest hits to date as it reached No. 1 on the Billboard Hot 100 chart and is one of Spotify's most-streamed songs of all time.

This isn't the first time Bieber has been slapped with a lawsuit for copyright infringement. In 2015, Bieber and Usher faced a $10 million suit by a pair of songwriters who claimed the duo lifted portions of their music without permission. A rep for Bieber did not immediately respond to Complex's request for comment.

You can compare "Sorry" and "Ring the Bell," as well as read Hinterland's full note on the matter below.

UPDATED, 7:11 p.m. EST: Skrillex just shared a clip of the original recording session with Julia Michaels, who helped write the song with Justin Tranter, Sonny Moore, and Michael Tucker. In it, you can see the producer adjusting the tone of her voice to what we hear on "Sorry" today. Watch it below.

UPDATED, 9:25 p.m. EST: Justin Bieber also addresses the lawsuit over "Sorry."