Sulli’s cause of death has been confirmed as a suspected suicide.
However, police are also exploring other possibilities.
A police official told Yonhap: ‘Choi seemed to have lived alone in the house.
‘It seems that she took her own life but we are also looking into other possibilities.’
The 25-year-old was found dead at her home in Sujeong-gu, Seongnam in the Gyeonggi province of South Korea by her manager.
Sulli’s manager had gone to Sulli’s home after he could not contact the star, with police later attending the scene.
The former f(x) star previously spoke about her struggles with anxiety, opening up about her mental health in her 2018 reality star Jinri Store.
Sulli – real name Choi Jin-ri – said: ‘Social phobia, panic disorder…. I’ve had panic disorder ever since I was young.
‘There were times when close people… Some of my closest friends have left me. People hurt me, so everything fell apart. I didn’t feel like I had anyone on my side or anyone who could understand me. So that’s why I completely fell apart.’
Sulli, who debuted with f(x) in 2009, left the girlband on hiatus in July 2014, after struggling with the abuse and malicious comments she received online.
She withdrew from the band officially a year later and turned her attention to acting, although Sulli made her solo debut in June this year with her single album Goblin.
Sulli was close friends with SHINee star and SM Entertainment label-mate Jonghyun, who took his own life aged 27 in December 2017.
Sulli was one of many stars who attended Jonghyun’s funeral.
Fans of the talented star have shared their heartbreak and condolences on social media as they come to terms with the shock news.
One fan tweeted: ‘Rest in peace for the beautiful and talented woman’, while other messages read ‘we lost another angel…’ and ‘You can finally rest now’.
Sulli debuted as a member of the girl band f(x) alongside bandmates Victoria, Amber, Luna and Krystal in September 2009 with the single La Cha Ta.
The Busan-born star had success with the girlband with songs including Pinocchio (Danger), Electric Shock and Hot Summer, before her hiatus was confirmed on 24 July 2014.
In addition to her successful music career, Sulli was an acclaimed actress, starring in Ballad of Seodong, The Pirates, Fashion King, Real To The Beautiful You and Hotel Del Luna.
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