UFC Hall of Famer Matt Hughes was badly injured in a car accident in Illinois on Friday when a truck he was in collided with a moving train, law enforcement tells TMZ Sports

We're told the accident occurred at 10:39 AM. Law enforcement says 1 person was transported to a hospital with serious injuries. Dana White says that injured person is in fact Hughes. 

Investigators are at the crash site trying to figure out what went wrong.

White says Hughes suffered head trauma and his family is on their way out to be with him.

Hughes is a UFC Hall of Famer -- a 2-time welterweight champion who beat stars like GSP, BJ Penn and Royce Gracie. He last fought in the UFC in 2011.

Earlier this year, he mulled a comeback. 

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