Three people were shot to death in a park when a family custody dispute turned violent as the boy at the center of the disagreement played baseball, authorities said.

The victims in Monday night's shooting were the paternal grandparents and maternal grandfather of the boy, authorities said. The boy's father was wounded in the shooting at a ballfield in Dandridge known locally as the Field of Dreams.

One gun was recovered, but authorities in the town about 30 miles east of Knoxville were waiting to assign blame.

"I don't think it was a murder-suicide," City Administrator James Hutchins said. But he added, "We don't know yet. We are waiting on autopsy reports."

As many as 75 people, including some children, were in the area when the shooting happened. Authorities were offering them counseling from a chaplain.

Police said the boy's grandparents, Ellen E. Shands, 62, and Jerry D. Shands, 63, and father, Jerry B. Shands, 39, were walking to their car when shooting erupted. Jerry B. Shands' former father-in-law, Samuel L. Noe, 61, was also present, police said.

Authorities refused to speculate about who fired the shots, but after it was over the three grandparents were dead and his father, who had legal custody, was flown by helicopter to the University of Tennessee Medical Center in Knoxville for emergency surgery. His condition was not considered life-threatening.

"Our preliminary investigation revealed that the shootings were not related to and did not stem from the ball game. It appears this was an ongoing family dispute," Dandridge Police Chief Carson Williams said.

Hutchins said the boy is about 9 or 10 years old and had played in the game, which pitted his fall youth league team from Jefferson City and a Dandridge team. Witnesses were being interviewed.

Authorities said a fifth person they refused to identify was present, but no charges had been filed against anyone. The boy's mother, who has remarried, was not believed to be at the game, Hutchins said.

The Tennessee Bureau of Investigation was assisting in the case.