Kyle Busch died after severe pneumonia progressed into sepsis, resulting in rapid and overwhelming associated complications, according to a statement released by his family.

Kyle Busch's family earlier Thursday announced he had been hospitalized with a "severe illness."

Kyle Busch, a two-time Cup Series champion who won more races than anyone across NASCAR’s three national series, has died. He was 41.

Busch, a two-time NASCAR champion, died at 41 on Thursday

Kyle Busch died after severe pneumonia progressed into sepsis, leading to rapid complications.

His family revealed the cause of death one day before he was set to race in the Coca-Cola 600 at Charlotte Motor Speedway.