(CNN) K-pop boy band BTS became the first Korean artists ever to appear on stage at the Billboard Music Awards on Sunday, as they performed their new single "Fake Love."

After Kelly Clarkson introduced them as the "biggest boy band in the world," the seven BTS members swept across the purple-lit stage in a choreographed routine. BTS fans, who call themselves the A.R.M.Y (Adorable Representative M.C for Youth), went wild, singing along and sometimes breaking into tears.

K-pop boy band BTS at the 2018 Billboard Music Awards in Las Vegas.

BTS also won the Top Social Artist award for the second year running, beating out superstars like Justin Bieber and Ariana Grande. The award honors artists with the highest fan engagement on social media, recorded and ranked on Billboard's Social 50 chart. As the group accepted the award, they thanked fans around the world in both English and Korean.

Popular K-pop groups like BTS have long had devout fan bases in South Korea and across Asia, but only began breaking into the American market recently. BTS made headlines last year as the first K-pop group ever to win a Billboard award, coming in ahead of some of the same big pop names as this year.

Since then, the boy band has continued its rise, selling out world tours, performing in Times Square on New Year's Eve and appearing on US talk shows like Ellen. Other K-pop groups like SHINee, Girls' Generation and Exo have enjoyed increasing global recognition, performing at the PyeongChang Winter Olympics and at international K-pop festival KCON.

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