Law enforcement vehicles were seen parked along Valleycrest Drive near the home of the rapper, whose real name is Malcolm James McCormick.
The Los Angeles County coroner said McCormick was found unresponsive in his home in the late morning hours. He was pronounced dead at the scene at 11:51 a.m.
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The coroner's van arrived on scene shortly before 2:30 p.m. Sometime around 4 p.m., McCormick's body was placed into the van.
His family released a statement regarding the hip-hop star's death, but did not release details on how he died.
Warner Bros. Records also released a statement, saying in part that McCormick was "a hugely gifted and inspiring artist."
— Warner Bros. Records (@wbr) September 7, 2018
The coroner said the cause of his death had not been determined and an autopsy was pending.
Back in May, McCormick was arrested for allegedly driving under the influence following a crash in Studio City.
McCormick and pop star Ariana Grande had broken up earlier that month, with Grande tweeting afterward: "pls take care of yourself."
pls take care of yourself
— Ariana Grande (@ArianaGrande) May 17, 2018
McCormick's last tweet was posted at 6:45 p.m. Thursday about his upcoming tour, set to begin in October at the Masonic in San Francisco.
Go get tickets for tour.
— Mac (@MacMiller) September 7, 2018
Thundercat
J.I.D.
I’m bringing a band.
The show is going to be special every night.
I wish it started tomorrow.
It starts October 27th.https://t.co/RGYZC5DTza
The Associated Press contributed to this report.