Celebrities like Rosie O'Donnell, Jimmy Kimmel, and Andy Cohen reacted to the news of Joan Rivers' death on Thursday, Sept. 4. Credit: Axelle/Bauer-Griffin/FilmMagic

Friends, family, fans, and celebrities took to social media on Thursday, Sept. 4, after learning of Joan Rivers' death at age 81 from surgical complications. Daughter Melissa Rivers confirmed her mother passed away in a statement which read: "She passed peacefully at 1:17pm surrounded by family and close friends." 

Find out what Joan's friends, admirers, and fans had to say about the late comedienne below.