Kim Shattuck, the guitarist, singer, and songwriter best known as the frontwoman for the Muffs, died Wednesday at age 56, NPR reports. Shattuck, whom Jezebel calls a "Los Angeles punk legend," had suffered from ALS for two years, though she never announced the diagnosis publicly. She formed the Muffs with Melanie Vammen in 1991 after leaving the Pandoras; the two later teamed up again to start the Coolies, which released its debut in July—and pledged all profits to an ALS nonprofit. Shattuck also often guested with underground punk bands, and was the bassist for the Pixies for five months in 2013. (She was "semi-famously fired" for crowd-surfing during a show, the AV Club reports.)
"Kim was a true force of nature," said the Muffs in a statement. "While battling ALS Kim produced our last album, overseeing every part of the record from tracking to artwork." It will be released Oct. 18. Vammen, who said her "heart is forever broken," shared an Instagram post from Shattuck's husband saying she had passed away "peacefully in her sleep." Many fellow musicians were mourning Shattuck, including quite a few who remembered her distinctive voice: "Shattuck screamed so sweetly, so savagely," writes Lars Gotrich at NPR, while Maria Sherman, who offers up a playlist of Shattuck classics at Jezebel, says she was known as the "possessor of that voice her entire career." (More punk rock stories.)