Logan Paul, KSI Pelted With Prime Bottles In Copenhagen

It was cloudy with a chance of Prime in Copenhagen on Monday ... 'cause Logan Paul and KSI's meet-up with fans came to an abrupt halt when they started getting rocked with bottles of their own drink line!!

The wild scene went down as the YouTube boxing enemies-turned-business partners were promoting their hydration beverages in Denmark ... when, for some reason, some members of the crowd decided they'd much rather chuck their handouts than consume them.

Now, the whole thing could easily be a publicity stunt to give Prime some free airtime ... and if that's the case, it worked -- 'cause here we are writing about it.

If you watch the video, it's clear the guys never felt they were in harm's way ... especially considering the security guards in attendance appeared to be smiling through the bottle attack as they moved the two social media stars out of the line of fire.