Riverhead police say they’re investigating a trespassing incident at Splish Splash after a video showing a group of BMX riders gliding down the water park’s slides went viral over Thanksgiving weekend.

The 15-minute video shows a group of young men entering the water park by hopping a barbed-wire fence and then riding their bikes around several Splish Splash attractions.

Billy Perry, 21, a BMX rider from West Islip with a large social media following, uploaded the video to his YouTube channel Sunday. It has been viewed more than 2.4 million times as of Wednesday afternoon.

“We talked about sneaking in and riding this water park for years. Thanksgiving Day came and it was finally time to head out at 6 a.m. in hopes of riding the water park and not getting arrested. The day was absolutely insane and then we got spotted by security,” Perry writes in the video’s description.

Perry did not return a request for comment.

“It’s very dangerous. It’s why we have no-trespassing signs posted all over the property,” said Mike Bengtson, Splish Splash general manager.

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Bengtson also said the trespassers caused “cosmetic and structural damage” to five of the park’s slides. The cost of repairs is still being assessed, Bengtson said.

Riverhead police say Splish Splash management reported the incident Monday. No arrests have been made, police said.