Agnes Tirop, Kenya's two-time world championship bronze medallist, has died at the age of 25 in an alleged murder at her home, with police seeking her husband.
Elgeyo Marakwet County police chief Tom Makori said they were searching for Tirop's husband after his family reported he had phoned them crying and asking for God's forgiveness for something he had done.
"There are revelations which came from her husband's family," Makori said.
Tirop was found dead at her home in Iten in western Kenya, a town renowned as a training base for distance runners.
Kenyan media reported she was found with stab wounds in her abdomen and neck.
Tirop's car, which was parked outside the home, had its windscreen and windows smashed, which could indicate a domestic dispute before she was killed, police said.
Kenya's National Police Service said Tirop was the victim of a "heinous crime" and promised "speedy and comprehensive investigations."
The Kenyan track federation had earlier said Tirop, one of her country's rising stars, had allegedly been stabbed by her husband but it was still working to uncover details of the incident.
"Kenya has lost a jewel... ," Athletics Kenya said.
International Olympic Committee president Thomas Bach described Tirop as "a young and bright talent", adding: "Her performances at the Olympic Games Tokyo 2020 gave hope and inspiration to so many people.
"My thoughts go to the Kenyan Olympic community and especially to her friends and family."
Sebastian Coe, the president of World Athletics, said: "Athletics has lost one of its brightest young stars in the most tragic circumstances.
"This is a terrible blow to the entire athletics community, but especially to her family, her friends and Athletics Kenya and I send them all our most heartfelt condolences."
International track governing body World Athletics said it was "deeply shocked and saddened" by Tirop's death.
Tirop won bronze medals in the women's 10,000m at the 2017 and 2019 world championships and finished fourth in the 5,000m at the Tokyo Olympics.
Just last month, Tirop broke the world record in a 10km road race in Germany.