Haruhi Suzumiya question. Who are the Radicals that Ryoko Asakura mentioned in The Melancholy of Haruhi-Chan Suzumiya?

I've re watched The Melancholy of Haruhi Suzumiya Anime series multiple times. Including all the spin off series. And I decided I'd re watch The Melancholy of Haruhi-Chan Suzumiya on DVD and Blu-Ray. And when it got to a scene in Episode 2 where Ryoko Asakura was attacking Kyon, And Yuki Nagato stepped in and stopped her, before Asakura-Chan disappeared, she mentioned that she was one of the few members of the Radicals. And that Kyon will be meeting the rest of them later on. The spin off series in the Anime didn't even show them in the spin offs. Not even the main series either. I've re watched this series many times. And this time I figured I'd ask about this, considering I found it strange that it never showed the Radicals at all. Was Asakura talking about the Anti-SOS Brigade members? I don't remember it showing the Radicals in the Manga either. I tried to Google it, but I got no answer at all. So I figured I'd ask about it. And see if anyone knows anything about this. Thank you all for the help in advance. I really do appreciate it. KyoAni Kyoto Animation Studios. Anime, Manga, Light Novel book series. And Video Games.