The 24-year-old set the world record, opens new tab at the Chicago Marathon in October with a time of two hours and 35 seconds to surpass the mark of 2:01:09 run by compatriot Eliud Kipchoge in Berlin in 2022.
Kiptum, who clocked three of the seven fastest marathon times in history, had been hoping to become the first man to run the marathon in under two hours in race conditions at Rotterdam in April as well as make his Olympic debut in Paris in July.
“We are shocked and deeply saddened to learn of the devastating loss of Kelvin Kiptum and his coach, Gervais Hakizimana,” World Athletics President Sebastian Coe said in a statement.
“On behalf of all World Athletics, we send our deepest condolences to their families, friends, team mates and the Kenyan nation.
“An incredible athlete leaving an incredible legacy, we will miss him dearly.”
According to the police report, Kiptum was driving his Rwandan coach and a woman in a car near the Rift Valley village where he was born when the accident occurred.
The athlete lost control of the vehicle and veered off the road into a ditch, travelling for about 60 metres along it before crashing into a large tree.
Kiptum and Gervais Hakizimana died at the scene but the woman, 24-year-old Sharon Chepkurui Kosgei Keiyo, survived with serious injuries and was treated at a local hospital.
Despite the late hour, tributes were paid to Kiptum by senior Kenyan politicians and government officials.
“Devastating news as we mourn the loss of a remarkable individual, Kelvin Kiptum, World Record holder and Kenyan athletics icon,” former Kenya prime minister Raila Odinga said on social media platform X.
“My deepest condolences to his loved ones, friends, and the entire athletics fraternity. Our nation grieves the profound loss of a true hero.”