Hilary Duff regrets her costume choice.

The “Younger” star and her boyfriend, Jason Walsh, caused controversy on Friday when they showed up to the Casamigos Tequila Halloween Party in Beverly Hills, California, dressed as a pilgrim and Native American, respectively.

Michael Kovac/Getty Images for Casamigos Tequila

“I am SO sorry to people I offended with my costume,” the 29-year-old actress tweeted. “It was not properly thought through and I am truly, from the bottom of my ❤️sorry.”

WATCH: Hilary Duff and Boyfriend Jason Walsh Make Red Carpet Debut In Controversial Halloween Costumes

I am SO sorry to people I offended with my costume.It was not properly thought through and I am truly, from the bottom of my ❤️sorry. — Hilary Duff (@HilaryDuff) October 30, 2016

Walsh also shared an apology, posting a photo on Instagram that read, “I meant no disrespect. I only have admiration for the indigenous people of America. In hindsight I would not have made that decision. I apologize to anyone I may have offended.”

https://www.instagram.com/p/BMMv_V6DAP6/

WATCH: Hilary Duff on Personal Trainer Boyfriend Jason Walsh: ‘We Have a Lot of Fun Together’

This controversy comes on the heels of Chris Hemsworth apologizing for wearing a Lone Ranger-inspired costume to a New Year’s Eve party last year.

Duff and Walsh confirmed their relationship in last month. Friday’s event marked their first public appearance as a couple.

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