"The Cook County Medical Examiner's Office has determined that additional studies are required to establish the cause and manner of death for 21-year-old Jarad A. Higgins," a statement from the office read, referencing the 21-year-old rapper's real name.
"Additional studies include cardiac pathology, neuropathology, toxicology and histology."
The Illinois native, who reportedly toured with Nicki Minaj earlier this year, suffered a "medical emergency" which caused him to have a seizure after landing at Chicago's Midway airport early Sunday morning, according to Chicago Police.
The health emergency occurred while investigators were searching the rapper and his entourage's luggage for weapons and drugs, authorities added, noting that "none of the subjects claimed ownership of the luggage."
Police further stated Narcan was administered to the rapper. The Chicago Tribune reported that he was rushed to a nearby hospital in Oak Lawn, Ill. and doctors pronounced him dead at 3:14 a.m.
The search resulted in the arrests of two of Juice WRLD's security guards, Fox News has confirmed.
Christopher Long, 36, of Buena Park, Calif., was arrested on one misdemeanor count of carrying and possessing a firearm in the first degree. The second guard in Juice WRLD's entourage arrested was Henry Dean, 27, of Chicago. Dean was charged with one misdemeanor count of carrying a concealed firearm in an airport and a second misdemeanor of sale and/or possession of a high capacity magazine and metal piercing bullets.
The rapper previously sang about dying young in a rhyme in his song "Legends."
"What's the 27 club? We ain't making it past 21," Juice sang. The "27 club" is a group of singers who all died when they were 27, including Kurt Cobain, Amy Winehouse, Janis Joplin and Jimi Hendrix.
The rapper reportedly was traveling to Chicago Sunday to celebrate his 21st birthday at a big bash with fellow artists later that night.
Juice WRLD rose to fame after releasing the songs "Lucid Dreams" and "All Girls are the Same," followed by his 2018 debut album "Goodbye & Good Riddance." "Lucid Dreams," the rapper's most popular song, amassed almost a billion streams on Spotify, WGN-TV reported.