For flipping officers off!

Lil Pump is currently being detained in Denmark after "flipping off cops."

Lil Pump learned a valuable lesson when he was traveling in Europe. He was in Denmark to perform a show and was feeling himself a little too much, deciding to flip cops off. TMZ broke the news that the lil' rapper is now locked up after his childish antics and was forced to cancel a show.

Sources close to the rapper told them ... "cops in Copenhagen detained him and his crew Tuesday for an unknown reason. We're told someone in the group was holding something illegal."

The rapper live-streamed part of the arrest. As of now, he has not been charged with anything. He should be released shortly.

The cops in Europe do not play. Lesson learned... we hope!