A father-of-five has been stabbed to death at a Wisconsin river following an argument with three other fishermen. Peter Kelly, a 34-year-old volunteer high school wrestling coach, was stabbed in the chest beside the St Croix River at 9.45pm on Tuesday as he fished with a friend. The two men were on the Minnesota side of the river when they heard three men being loud and rude on the Wisconsin side and asked them to quieten down, authorities said. For the next three hours, Kelly and his friend exchanged heated words with the three other anglers. Scroll down for video . Loss: Peter Kelly, 34, was stabbed in the chest after he and a friend asked a group of rowdy fishermen to be quiet at a river on Tuesday. The argument escalated and Kelly was attacked and died at the scene . 'The group on the Minnesota side was making statements like, 'Why don't you clean up your act',' . Captain Steve Smith with the Polk County Sheriff's Office in Wisconsin told CBS Minnesota. 'The challenge was made – 'why don't you come over here?'' Kelly and his friend drove to Interstate Park on the Wisconsin side, where the argument escalated and one of the men pulled out a knife and stabbed Kelly in the chest. He died at the scene. After the stabbing, the attackers fled the scene and authorities are still searching for them. The Polk County Sheriff's Office said the three men are believed to be in their late teens or early 20s and were with a dog named Gunnar, who was either a golden retriever or a yellow lab. They were traveling in two vehicles with Minnesota license plates: a blue Chevrolet S-10 pickup truck and a small passenger car. Left behind: Kelly and his wife Christie, pictured, have four sons and a daughter all under the age of nine . Authorities are also asking for help tracking down five people who were in the area at about 7.30pm as they have witnessed the argument that ultimately escalated. Now his small community in St Croix Falls, which has just 2,100 people, is mourning the loss of the family man who volunteered as a coach at the high school's football, baseball and wrestling teams. He would often go to work at 4am so he could get back in time to coach before dinner, fellow high school coach Dan Clark told the Star Tribune. His day job was at Andersen Windows in Bayport, where he worked in quality control. 'He worked 10 to 12 hours a day at Andersen Windows, and he would come home and volunteer four hours a night to our wrestling program for four or five months a year,' Clark toldFox9. 'He was one of the greatest human beings that I ever hoped to meet.' His wife, Christie, stayed at home to care for their children, who are all under nine. They have four boys, Kellen, Payton, Miles and August, and last year welcomed a baby girl, Molly. Devastated: His brother, Mike Kelly, said the man's children did not understand what had happened . Confrontation: Kelly and a friend were on the Minnesota side of the St Croix River, pictured, and told men on the Wisconsin side to stop making so much noise. Kelly was stabbed at Interstate Park . 'I don't think they fully understand the implications of what happened,' his brother, Mike Kelly, told KARE. 'His daughter will never even get to know him.' Friends and family added that they do not believe Kelly was to blame for the confrontation. 'He did good things, and did what was right all the time,' his brother added. 'And that's probably what cost him. Some knuckle heads swearing and being silly.' Anyone with information about the incident is asked to call the Sheriff's Office at 715-485-8300. A GoFundMe page has also been set up for the family.
Peter Kelly and a friend were fishing on the Minnesota side of the St Croix River on Tuesday when they heard three rowdy men across the water.
They asked them to be quiet and an argument ensued for three hours.
The three men asked Kelly and his friend to come over so they drove to the Wisconsin side, where a fight unfolded and Kelly was fatally stabbed.
Kelly, who volunteered as a high school wrestling coach in his spare time, leaves behind a wife and five children, all under the age of nine.