Sung Si Kyung said, "Last week, the video of Shin Dong Yup's rampage went viral. At my concert, I was singing the last song and headed out towards the audience, and this guy with big and thick hands suddenly grabbed my chest. I was so surprised. When I realized what was going on, I saw Shin Dong Yup getting carried out by the guards." 

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Shin Dong Yup then explained, "I wanted to surprised Sung Si Kyung so I sneaked into the concert hall in the middle of his performance." 

In the fancam video that went viral, you can see MC Shin Dong Yup sneakily approaching Sung Si Kyung with a mischievous smile across his face and his hands stretched out. When the guards spot Shin Dong Yup, they proceed to lift him up and carry him away from the singer, who then shouts out, "Ahjussi!"

What's even more hilarious is that all this happened in a matter of seconds.