Police found the star's body at his New York apartment on Friday evening after he had suffered a reported drug overdose.
Lohan wrote, "I can't believe this.. i'm in shock. why? why? r.i.p. adam."
Diddy added, "DJ AM rest in peace."
Kelly Osbourne wrote, "I just cant believe that adam (dj.am) is gone i dont want to believe it im in shock. he was one of the most genuine people i have ever met!"
Shanna Moakler, whose ex-husband Travis Barker survived a plane crash with Goldstein last year, was among the first to Tweet, writing, "My deepest condolences for DJ AM, you were a great artist and will be severely missed. My thoughts and prayers to his family and friends."
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