Korean pop star Sulli, 25, was found dead in her home in Seoul on Monday.
The singer, whose real name is Choi Jin-ri, was found by her manager, who called authorities. Her cause of death is being investigated, but it is believed she took her own life, according to police.
"So far, it seems she killed herself, but we will leave all possibilities open and investigate," a police official said.
Her manager had made several attempts to reach the star the night before she was found and showed up to her home after not hearing from her, authorities said. Police said they found a note but haven't yet "analyzed its contents," CNN reported.
Sulli had battled depression and often spoke about cyber bullying. She started out her career as a child actress in 2005 and then transitioned into music as part of the K-pop girl band f(x).
She quit the band in 2014 after expressing she was overwhelmed and mentally exhausted from being the victim of cyber bullying.
The star then began to focus solely on acting, appearing in several television shows.
In 2018, Sulli spoke out about her struggles with panic disorder. This past June, she also became the co-host of the TV show “The Night of Hate Comments,” in which celebrities discussed their reactions to hateful comments and rumors online.