The 25-year-old 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.
Tirop won bronze medals in the women’s 10,000 meters at the 2017 and 2019 world championships and finished fourth in the 5,000 meters at the Tokyo Olympics. Just last month, Tirop broke the world record in the women-only 10-kilometer road race in Germany.
Her career took off when she won the world cross-country title in 2015 at the age of 19 to become the second-youngest champion in the event.
Kenyan President Uhuru Kenyatta urged police “to track down and apprehend the criminals responsible for the killing of Agnes.”
“It is unsettling, utterly unfortunate and very sad that we’ve lost a young and promising athlete,” Kenyatta said in a statement. “It is even more painful that Agnes, a Kenyan hero by all measures, painfully lost her young life through a criminal act perpetuated by selfish and cowardly people.”
International track governing body World Athletics said it was “deeply shocked and saddened” by Tirop’s death.
ArLuther Lee contributed to this report for The Atlanta Journal-Constitution.