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TikTok teenagers and K-Pop fans claimed responsibility for thousands of empty seats at President Donald Trump's first campaign rally in 3 months on Saturday night.

Trump is accustomed to speaking before packed arenas during his campaign rallies, but Saturday night's rally at the BOK Center in Tulsa, Oklahoma was barely half full. The BOK Center has a 19,000-seat capacity.

The half-empty arena almost looked like a Beyonce and Jay-Z concert tour.

Trump's campaign manager, Brad Parscale, had boasted on Twitter that the campaign received requests for more than 1 million tickets.

But reporters at the event on Saturday quickly noted the attendance was much lower than expected. Trump's campaign had events planned for the overflow crowd that was expected outside the arena. But the events were cancelled because there was no overflow crowd.

Within minutes after the rally ended, hundreds of teens took to TikTok to take responsibility for the embarrassing turnout.

The teenagers claimed they registered thousands of free tickets to the rally using their cellphones after @TeamTrump posted a tweet on June 11 asking supporters to register for free tickets.

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Fans of the Korean pop group BTS encouraged other teens to register for the rally -- and then not show up.

"It spread mostly through Alt TikTok — we kept it on the quiet side where people do pranks and a lot of activism," said YouTuber Elijah Daniel, 26. "K-pop Twitter and Alt TikTok have a good alliance where they spread information amongst each other very quickly. They all know the algorithms and how they can boost videos to get where they want."

Daniel said the teens deleted their posts so the news media wouldn't catch on to their plan and alert the Trump campaign.

"The majority of people who made them deleted them after the first day because we didn't want the Trump campaign to catch wind. These kids are smart and they thought of everything."