POPLAR BLUFF, Mo. (AP) — A southeast Missouri mother and father have been charged with killing a man who attacked the couple’s 12-year-old son during a monster truck event.

Brenda Michelle Holt, 40, and Rickey Brunell Holt, 39, of Bunker, Missouri, were freed on bond Monday. They are charged with felony voluntary manslaughter in the death of 41-year-old Joe Girard of Oak Ridge. No attorneys are listed for them in online court records, and a woman who answered the phone at their home said she had no comment.

Butler County Sheriff Mark Dobbs said the melee started Saturday when Girard slapped or punched the boy while people were camping at Brick’s Off-Road Park in Poplar Bluff during the “Trucks Gone Wild” event, The Daily American Republic reports. Witnesses described Girard as highly intoxicated and said he then began tearing up the camp. Dobbs said the boy fled to a family friend who was standing nearby and that another family friend then hit Girard several times. Dobbs said the boy’s mother and father then showed up at the camp and began beating Girard.

Dobbs said that witnesses reported Rickey Holt “jumped on the man’s head with both feet.” Dobbs said Brenda Holt also was intoxicated and tripped over the unconscious victim at one point, making her husband think Girard had knocked her down. Dobbs said that “fueled the beating even further.” Witnesses said Girad was in and out of consciousness during the assault.

Dobbs said that at one point, Girard’s friends fought through a large crowd that had gathered to watch the beating, put Girard in the back of a truck and drove him to emergency personnel.

“Defending yourself is one thing, but this is way outside the line,” said Dobbs, who indicated officers did not see any visible injuries on the Holts’ child.

Investigator Brandon Lowe wrote in the probable cause statement that Brenda Holt said her husband took off running after her son ran across a field and said he’d been hit in the face. She said she loaded her children into her vehicle and followed behind. She said she then kicked Girard in the head after he denied hitting her child because she was “upset over her child being assaulted.”

Lowe said Rickey Holt reported that when he saw Girard on the ground, he “’blacked out’ and began punching Girard because his son had been struck. Lowe wrote that one witness said that Rickey Holt struck Girard about 20 times.

Butler County Coroner Andy Moore said the autopsy shows that Girard died from asphyxiation after his larynx was fractured and a neck bone broken.