He hits her around 13 seconds and pulls her either by her hair or shirt.
Apparently the incident took place back in 2009 and Korean fans hid this video
to protect him. Here's proof that it is him and not a security guard like
many of his fans are now trying to claim.
Also a video of him on the same day with the same exact shirt and hairstyle for those who are still in denial.
SOURCE
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SOURCE