No other information is available at this time.
Police say the pickup was traveling on a road in central Illinois Friday when the driver crossed railroad tracks marked with a warning. UFC president Dana White, who was in touch with Hughes' family, told ESPN that Hughes had suffered head trauma in the accident.
"Officers with the Illinois State Police Crash Reconstruction Unit are investigating the crash".More news: Apple's making an Amazon Echo competitor called 'HomePod'
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Hughes dominated the UFC welterweight division for the better part of a decade when he exploded into the octagon by winning the belt with his now-historic KO win over Carlos Newton in 2001.
A two-time champ, he is a member of the UFC Hall of Fame.
Hughes (45-9), who beat some of the promotion's most renowned fighters, including George St-Pierre, B.J. Penn and Royce Gracie, resides in IL.
This is a developing story and updates will be posted as more details are released.