EAU CLAIRE, Wis. -- A truck involved in an Eau Claire mud competition has left the track, plowing into spectators and sending five people to hospitals with unspecified injuries.

The vehicle was involved in the Pioneer Days Mud Bog. The Eau Claire County sheriff's department says the vehicle left the course about 12:30 p.m. Saturday and collided with several people.

At least one person had to be extricated. Four of the injured were taken to a hospital by ambulance. The fifth was driven by a family member.

The victims' names haven't been released. They've been identified only as men aged 59, 42 and 28; a 22-year-old woman; and a 6-year-old boy.

Deputies and fire officials were already at the scene when the crash happened.

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