The victim was found dead by his truck in the middle of the interstate.
Northbound Highway 291 and I-470 were closed in the area of Colbern Road and Douglas Street, respectively. He was also an aspiring dirtbike racer.
Witnesses told police that Harter had been arguing with another person before his death and a second vehicle had been stopped in front of Harter's truck.
Hazy accounts of two men arguing and the vague description of a vehicle speeding north down a Missouri highway are the best leads investigators have as they hunt a mysterious man believed to have stabbed a young Air National Guard member to death Saturday in an apparent road rage murder. Police said they believe the suspect stabbed Harter and jumped back into his auto fleeing the scene.
Police said that Harter then stumbled back roadside and into traffic where he was found dead.
The dispute escalated and the unidentified motorist allegedly stabbed Harter before fleeing in his vehicle north on I-471, police said.
Air France-KLM shares plunge as CEO to quit amid labour dispute
The offer was open until 4 May, but did not receive the number of signatures required for it to be implemented. Air France-KLM reported a net loss of €269 million ($321 million) in the first quarter of the year.
This is the victim's 2003 Chevrolet Silverado extended cab Z71 edition. At the time of the incident, the victim had a large, zero-turn lawnmower in the bed of the truck.
Authorities are asking anyone who may have been driving down Interstate 470 or seen Harter's truck on 291 Highway around 7:30 p.m. Saturday to call police at 816-969-1705.
On Sunday, members of Harter's family pleaded for help in catching the man who stabbed Harter. He also helped with hurricane relief a year ago. He loved everyone. He would help anybody.
His mother said Harter had a lawn-care business and had one semester left until he graduated with an engineering technology degree. "He was a person".
"I can only imagine someone was upset because he wasn't going fast enough", she added. "But that's not a reason to take his life and leave him there".
'He would do anything to help anyone at the drop of a hat, ' his sister Kylee Harter said. "For someone to just take everything from him. He realized joy. He knew love", she said.