Cops showed up at R. Kelly's birthday celebration at a Chicago nightclub, responding to a call about a warrant for the singer's arrest ... TMZ has learned.
Kelly was partying his ass off at V75 Chicago early Thursday morning when cops say someone dropped a dime ... calling them to say Kelly was there, and had a warrant for his arrest. Check out the police dispatcher putting the call out to Chicago PD units.
Law enforcement confirmed to TMZ they did indeed go to the club and made contact with Kelly -- however, once they determined there was NO actual arrest warrant ... Kelly was free to go about his business.
It's unclear if the caller was just pranking Kelly, or if the person really thought there was an arrest warrant ... but cops tell us they routinely respond to such calls ... just to make sure.
As for Kelly's party ... it was a pretty wild scene.
He was surrounded by screaming fans as he grabbed the mic and declared, "I don't give a f**k about what's going on!!" -- a clear reference to the controversy swirling around him after the airing of "Surviving R. Kelly."
Strange as it sounds ... Kelly had tons of fans on hand gassing him up as he sang the opening to "Bump N' Grind."