Kenya's marathon world-record holder Kelvin Kiptum and his coach have been killed in a traffic accident in the Rift Valley, cutting short the promising career of the only man to have run the endurance classic in less than two hours and one minute.

The 24-year-old set the world record at the Chicago Marathon in October with a time of 2:00:35, surpassing the mark of 2:01:09 run by his compatriot Eliud Kipchoge in Berlin in 2022.

Kiptum, who has clocked three of the seven fastest marathon times in history, was hoping to become the first man to run the marathon in less than two hours under race conditions, as well as make his Olympic debut in Paris later this year.

"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, teammates and the Kenyan nation.

"An incredible athlete leaving an incredible legacy, we will miss him dearly."

According to The Nation newspaper, Kiptum was driving his Rwandan coach and a woman in a car in the Rift Valley late on Sunday evening when the accident occurred.

Kiptum and Hakizimana died at the scene but the woman, Sharon Kosgey, survived with serious injuries and was treated at a local hospital.

"This was a self-involved accident," the newspaper quoted the local police commander, Peter Mulinge, as saying.

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 Kenyan prime minister Raila Odinga said on social media.

"My deepest condolences to his loved ones, friends, and the entire athletics fraternity. Our nation grieves the profound loss of a true hero."

Kenya's Sports Minister Ababu Namwamba said he was sickened by the news.

"Kenya has lost a special gem. Lost for words," he posted on X.

David Rudisha, Kenya's two-time Olympic champion in the 800 metres, posted on social media of his shock at the news.

"This is a huge loss," Rudisha wrote.

Later, International Olympic Committee (IOC) president Thomas Bach also expressed his shock.

"It is with extreme sadness that I learnt of the tragic passing of world marathon record-holder Kelvin Kiptum from Kenya in a car accident," Bach said on the IOC account on X.

"We had been looking forward to welcoming him into the Olympic community at the Olympic Games Paris 2024 and seeing what the fastest marathon runner in the world could achieve."