One of the stars of MTV's "Rob & Big" has died.

Christopher "Big Black" Boykin, 45, died Tuesday. No cause of death has been announced, but TMZ reported that multiple sources said it was likely a heart attack that killed the reality television star.

Boykin was best known for being the best friend and body guard of professional skateboarder Rob Dyrdek. The pair both appeared in "Rob & Big" and "Fantasy Factory." 

Boykin, who served in the U.S. Navy prior to being on television, has a 9-year-old daughter, TMZ said.