Further details are now unclear.
A rep for Miller did not immediately return a request for comment.
Los Angeles police said they responded to a report of a deceased person at a home on the same block where Miller is listed as a resident, and had turned the case over to the coroner's office.
"I was just getting super fat, and I didn't wanna be on national TV and fat, so I stopped sippin" lean", he told Noisy.
"I respect and adore him endlessly and am grateful to have him in my life in any form, at all times regardless of how our relationship changes or what the universe holds for each of us". That's fine, that's good, that's life.
Miller had been in a long-term relationship with Ariana Grande, which ended this past May.
Following that arrest, his former partner Ariana Grande posted a message to McCormick saying: "Please take care of yourself".
The artist released a new album last month titled "Swimming", and was scheduled to begin his tour next month, ABC Action News reports. It was set to kick off on October 27 in San Francisco, California. "The show is going to be special every night".
"Do I wish that every single thing I did when I was 19 wasn't a discussion? Yeah. But am I a drug addict? No".
Added pop singer Shawn Mendes: "Unreal".
As his career progressed, critics noted an expansion in Miller's approach to music to include more singing, more serious themes and dark, dense production. "It's very sad. We've been having numerous phone calls from fans all over the world who are sharing their grief with us".
Miller had spoken openly in the past about a long-time struggle with substance abuse.
The prolific American rapper has died at the age of 26.