The Rolling Stones haven’t been playing their controversial 1971 song “Brown Sugar” during the ongoing No Filter Tour. We now have a reason, according to The Daily Mail.

Activists reportedly targeted the band's largest fan site, posting about the Sticky Fingers track's references to slavery — and ultimately prompted its disappearance from set lists.

The publication reports that “a group of campaigners posed as hardcore Stones superfans” in order to access the 40-year-old subscription service IORR (a nod to “It’s Only Rock ’n’ Roll”), posting messages on discussion threads criticizing “Brown Sugar.” The fallout reached management, and reportedly informed the band’s decision to retire the song.

Keith Richards addressed that notable omission in a recent interview: “You picked up on that, huh?” he told the Los Angeles Times. “I don’t know. I’m trying to figure out with the sisters quite where the beef is. Didn’t they understand this was a song about the horrors of slavery? But they’re trying to bury it. At the moment, I don’t want to get into conflicts with all of this shit."

The guitarist couldn't say if "Brown Sugar" would ever return, adding only that he's "hoping that we'll be able to resurrect the babe in her glory somewhere along the track.”

Fan site founder Bjornulf Vik said Richards’ use of “sisters” appears to reference a group of female activists whom The Daily Mail says “have aggressively targeted unsuspected fans over recent weeks.” He reportedly shut down IORR’s subscription service and is attempting to remove the activist members.

"IORR has been spammed by political posts related to 'Brown Sugar' lately," Vik confirmed. "Like many other things, some people do make this a highly political discussion. It seems like it is impossible for some to discuss 'Brown Sugar' without getting highly political and offensive."

When the Los Angeles Times asked Mick Jagger about the song’s stage shelving, he offered a more vague answer than his bandmate: "We've played 'Brown Sugar' every night since 1970, so sometimes you think, 'We’ll take that one out for now and see how it goes,'" he said. “We might put it back in.”

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