Celebrities flocked to Twitter Saturday after news broke that Grammy Award-winning singer Amy Winehouse was found dead in her London home.
It is suspected that Winehouse suffered a fatal drug overdose but an official cause of death will be determined by an autopsy, to be performed Sunday.
Winehouse has publicly battled both drug and alcohol addiction, and was most recently admitted to a rehab facility back in May.
Celebrities, including Demi Moore, Sophia Bush, Anderson Cooper, and Winehouse's close friend Kelly Osbourne mourned the late singer on the social networking site.