Two brothers were killed and an 11-year-old was injured at a weekend mudding event in Middle Georgia.

According to the Georgia State Patrol, a driver at Saturday night’s South Creek Mud Boggin’ event in Milledgeville lost control of his truck due to a mechanical failure and hit brothers Ryan and Justin Moore of Macon and Zach Holloway of Milledgeville.

Ryan, 14, and Justin, 10, were pronounced dead at the scene. Zach, a relative of the brothers, was flown to a medical facility in Jacksonville, Fla.

GSP spokeswoman Franka Young said the driver, Tommy Howell, 50, of McRae, of a 1988 Chevrolet S10 was completing his run through the mud pit and preparing to exit when the throttle of the vehicle stuck and the driver was unable to slow down.

“He lost control of his vehicle as he exited the mud pit,” she said. “The vehicle traveled through a cabled area and struck three small children before it overturned and came to an uncontrolled stop.”

MORE: What is mud bogging, and what happens at a mudding competititon?

The GSP is conducting an investigation.

“Our Mud Boggin’ family is heartbroken,” event officials said on Facebook. “There are no words that can ever be said to even begin to express our sorrow.”

In other news:

The victim came in contact with the suspect just moments before, inside Shell Gas Station on Buford Highway.