BALSAM LAKE, WIS. – A father of five is dead and a Minnesota teenager barely out of high school is in jail for stabbing him, yet authorities still can't say with certainty what fueled a three-hour argument that preceded the fatal clash between St. Croix River anglers Tuesday night.

The Polk County attorney's office charged Levi C. Acre-Kendall, 19, of Cambridge on Friday with first-degree reckless homicide in the death of St. Croix Falls resident Peter S. Kelly. But authorities say it's unclear how Kelly, 34, and a friend became embroiled in a running confrontation with Acre-Kendall and his two friends as they fished on opposite riverbanks in Interstate Park.

"All I can tell you is that it would have never happened if it weren't for those two older men coming to the boys, because the boys were just fishing," Acre-Kendall's mother, Lavonne Acre, said through sobs Friday morning. "Levi's a good kid."

Polk County Sheriff's Chief Deputy Steve Moe said that despite cooperation from Kelly's and Acre-Kendall's friends, authorities don't know what started the dispute or what exactly was said.

Attorney David Sjoberg, who accompanied Acre-Kendall when he turned himself in Thursday to authorities in Balsam Lake, said he had no "clear sense" of the details of the argument.

"It doesn't sound like it was a dispute about anything other than some silly stuff," he said.

The criminal complaint also shed little light on how it started. Instead, it gave conflicting accounts of the deadly encounter:

Kelly's friend, Ross Lechman, said the young men were standing outside a car when Acre-Kendall allegedly stabbed Kelly in the heart.

Acre-Kendall's two friends, ages 19 and 17, told authorities that Kelly tried to pull Acre-Kendall out of a car as the younger men attempted to flee. That's when Acre-Kendall stabbed Kelly, they said.

What is undisputed is that Kelly and Lechman were fishing on the Minnesota side of the river about 6:30 p.m. when the argument began with Acre-Kendall and his friends, who were fishing on the Wisconsin side. About three hours later, the complaint said, Kelly and Lechman drove over to confront the other men.

Lechman said that one of the men stepped between Acre-Kendall and Kelly to defuse the situation.

Kelly asked Acre-Kendall whether he had pulled a knife, the complaint said. Lechman said that Kelly and Acre-Kendall argued. Then, Kelly ran back toward his own vehicle.

"We got to go," Kelly said. "He stabbed me."

Lechman asked Acre-Kendall whether that was true.

"Yes, yes I stabbed him," Acre-Kendall said, according to Lechman's account.

Kelly was stabbed about 9:45 p.m. The young men fled.

Sheriff Peter Johnson said Kelly was unable to provide any information before he died less than an hour later at a hospital.

Authorities zeroed in on Acre-Kendall as a suspect after finding receipts at the scene, reviewing store surveillance video and receiving a tip from a concerned parent who knew the young men.

That parent said that five young men had been fishing at Interstate Park over the weekend.

Acre-Kendall's mother turned over to police the alleged murder weapon and the clothes her son wore that night.

District Attorney Dan Steffen said Acre-Kendall's friends have cooperated and are being treated as witnesses, not suspects. That, however, could change.

Johnson said his office is still investigating and will present findings to Steffen's office to determine whether other charges are merited.

Kelly's brother, Michael Kelly, who was not at the scene, has said the younger men were shouting profanities and slurs across the river, prompting his brother to ask them to leave the spot, which is popular with families. He also said the young men were smoking marijuana, an allegation Johnson declined to address.

Friday afternoon, Acre-Kendall made his first appearance in court, where bail was set at $125,000. His next hearing is Wednesday.

"He's a young kid, but I don't feel for him at all," Michael Kelly said of Acre-Kendall. "I see … five young kids at home waiting for their father."

Funeral services for Peter Kelly are planned for Saturday at Our Lady of the Lakes Church in Balsam Lake.

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