Stars took to Twitter on Friday to mourn electronic dance music star Avicii, born Tim Bergling, who died in Muscat, Oman, at the age of 28.
He'd been in failing health for several years and had retired from live performances in 2016.
Just this week, he was nominated for a Billboard Music Award for his 2017 EP Avici (01).
Avicii was best known for his global smash "Wake Me Up," featuring vocals by Aloe Blacc, who was introduced to the DJ through Mike Shinoda from Linkin Park. Then, Aloe told ABC News in 2013, "Avicii called me up and said, 'Hey I'm over at Mike Einziger's house -- from Incubus -- would you like to write a song?' So I headed down and we went to the studio and wrote 'Wake Me Up' and we did it in, like, four hours."
Explaining the song's appeal, Aloe said, "I feel like the lyrics are very nostalgic ... if you're older, it makes you feel like back when you were maybe prepubescent or middle school. If you're young, it makes you feel like it's time for you to break out of your shell and live life. So I think it just hits everybody in their own interpretive way."
Here are some of the reactions:
Charlie Puth wrote, "Wow, I would like to take a moment to pay tribute to the man who really opened my eyes as to what my productions could one day sound like. @Avicii was a genius and a music innovator, and I can not believe he is no longer with us. RIP to the very best."
Liam Payne: "Oh my god truly devastated for Avicii very very sad news way to[o] young ... what a talent he was. rest in peace x."
Dua Lipa: "Such sad news to hear about Avicii passing. Too young and way too soon. My condolences go out to his family, friends and fans x."
Dan Reynolds of Imagine Dragons: "devastated at the news of @Avicii passing. working with him was one of my favorite collaborative moments. far too young. the world was a happier and fuller place with his presence and art. sending all my love to his friends and family. Xxdr."
Fellow EDM superstar Calvin Harris: "Devastating news about Avicii, a beautiful soul, passionate and extremely talented with so much more to do. My heart goes out to his family. God bless you Tim x"
Fellow EDM superstar Deadmau5: "my sincerest and most heartfelt condolences to the friends, fans and families of @Avicii :( Banter aside, nobody can deny what he has accomplished and done for modern dance music and im very proud of him."
Marshmello: "At a loss for words...Rest easy brother."
Adam Lambert, who worked with Avicii and CHIC frontman Nile Rodgers on the DJ's 2013 song "Lay Me Down": "RIP Tim. You were a brilliant composer and a gentle spirit. Fond memories of creating music w @Avicii and @nilerodgers."
Nile Rodgers: "#RIPAVICII Dear Tim your family have my most heartfelt condolences. You were my little bro. Love always."