Frontwoman of pioneering all-girl punk outfit The Slits Ariane “Ari-Up” Forester (a number of different spellings for her proper name appear across the web and from official sources) died yesterday after battling with what has only been described as “a serious illness.” The news was released on the website for Sex Pistol’s and Public Image Ltd.’s frontman, John Lydon (who is Forester’s stepfather), saying, “John [Lydon] and Nora [Forester] have asked us to let everyone know that Nora’s daughter Arianna (a.k.a. Ari Up) died today (October 20) after a serious illness. She will be sadly missed. Everyone at JohnLydon.com and PiLofficial.com would like to pass on their heartfelt condolences to John, Nora, and family. Rest in peace.” Ari Up was an important musical figure as the offbeat, dreadlocked founder of The Slits and New Age Steppers, and we were lucky enough to interview the inimitable vocalist just over a year ago, which you can read here. In her memory, we’ve included some of our favorite videos of The Slits, including the never-before-released “Lazy Slam,” below. Our thoughts go out to Ari Up’s friends and family in this difficult time.

“Lazy Slam”

“Instant Hit”

“Typical Girls”

“Heard it Through the Grapevine” (Live)