Rapper and rising superstar, Juice WRLD, has died after suffering a seizure at Chicago’s Midway airport on Sunday morning, TMZ reports.

Juice WRLD—whose birth name is Jarad Anthony Higgins—was returning home to Chicago from California. According to witnesses, the rapper got off the plane then had a seizure while walking through the airport. Law enforcement insiders tell TMZ that he was bleeding from the mouth when paramedics arrived on the scene but was still conscious. Emergency responders rushed Juice to the hospital where he was pronounced dead a few moments after arriving at the facility. At this point, Juice WRLD’s cause of death is still unknown. He turned 21 years old on Dec. 2.

Juice WRLD caught mainstream attention in 2018 with his smash single, “Lucid Dreams.” The track peaked at No. 2 on the Billboard Hot 100 chart. While “Lucid Dreams” blended rock melodies to make a trap ballad, Juice WRLD also captivated audiences with his impressive command of lyricism. His ability to freestyle on command for extended periods of time generated him a cult-like following. This versatility led many to believe that he would become one of the biggest stars in the world. Close collaborator, fellow Chicagoan, and friend G Herbo, likened Juice to the legendary Michael Jackson and his management team also compared him to legends.

‘I totally believe, deep in my heart, that he is the GOAT and the only person that can take the throne away from you, or whoever else you want to put at the top of the rap game—if it is Travis, if it is J. Cole. I feel like he is the future of this rap shit,” his day-to-day manager, Peter Jideonwo, told Complex. “It could take him five years, but I think he is going to get there, and that throne is gonna be his.” His label manager, Lil Bibby, added: “He records like Future and Young Thug, but better. I’m vouching for him like that.”