(CNN) The name BTS may not be familiar to the majority of Americans, but that didn't stop the South Korean boy band from making history Sunday night, when they became the first K-pop group to clinch a Billboard Music Award.

Beating out US favorites Justin Bieber, Selena Gomez, Ariana Grande and Shawn Mendes, BTS scooped the Top Social Artist award at a lavish ceremony in the T-Mobile Arena in downtown Las Vegas.

"We still cannot believe that we're standing here on this stage at the Billboard Music Awards," said BTS member Kim Nam-joon, known to fans as "Rap Monster," onstage. "It is so great to see all the artists we admire, and we feel honored to be in this category with all these great artists right in front of us."

BTS's group award follows South Korean trailblazer PSY, who became the first K-pop solo artist to win at the Billboard Music Awards back in 2014, for Top Streaming Song, "Gangnam Style."

BTS fans, known as the "A.R.M.Y." (Adorable Representative M.C's for Youth") voted for the award on Twitter and on the awards website, using the hashtag #BTSBBMAS more than 300 million times.

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