Too late now to say sorry? Justin Bieber, Skrillex sued for copyright infringement

Justin Bieber and Skrillex have been sued for copyright infringement by singer-songwriter Casey Dienel for the multi-platinum song Sorry.

Dienel, who performs as White Hinterland, filed suit against the two performers and their publishing companies, Universal Music and co-writers in federal court in Nashville, Tennessee, on Wednesday.

"As many of you that follow my career and work have already recognized, Justin Bieber's song Sorry copies the vocal riff prominently featured in my song Ring the Bell," Dienel wrote on Facebook.

"Like most artists that sample music, Bieber could have licensed my song for use in Sorry. But he chose not to contact me ... In the end, I was left with no other option. I believe I have an obligation to stand up for my music and art."

Her suit claims Sorry copies a prominent vocal riff from her song Ring the Bell, released in 2014, and loops it. Dienel's lawsuit said her attorney sent a letter to Bieber's lawyer and manager explaining the infringement but they didn't respond.

Representatives for Bieber and Skrillex didn't immediately return requests for comment Friday.

Dienel is asking for unspecified damages and attorney's fees.

Dienel's song was released on her album Baby in 2014 on the independent record label Dead Oceans.

In a 2014 review, Rolling Stone magazine praised Dienel's vocal ability.

"She's got a Mary Poppins-size bag of tricks, singing in operatic quivers, howling yelps, haunting harmonic layers and even full-on vocal fry without showing any seams," wrote reviewer Cady Drell. "Dienel's vocal acrobatics stay riveting."