(CNN) In a moment BTS fans had been waiting for, the South Korean boy band took over New York City's Central Park for an outdoor concert.

The Bangtan Boys kicked off "Good Morning America's" 2019 Summer Concert Series on Wednesday morning and many of their fans -- known as the ARMY -- had camped out in the rain for days to catch a glimpse of the group.

"Thank you for waiting for days (in the rain, cold, everything)," band member RM said.

Those sentiments were echoed by bandmate V, who told the crowd, "Our fans are the best. They are motivation. We love you ARMY!"

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