Agnes Tirop, Kenya's two-time World Championship bronze medallist, has been found stabbed to death at her home in Iten.
Police said they are on the hunt for her husband after the attack at Tirop's home in the high-altitude training hub in western Kenya.
Tirop was a double World 10,000m bronze medallist and 2015 World Cross Country champion, who also finished fourth in the 5,000m at the Tokyo Olympics this year.
Last month, she smashed the 10km world record at the Road to Records event in Germany, with a time of 30:01, slicing 28 seconds off the previous record.
Tirop also made history in 2015 when she became the second-youngest ever gold medallist in the World Cross Country Championships after Zola Budd.
"Kenya has lost a jewel who was one of the fastest rising athletics giants on the international stage, thanks to her eye-catching performances on the track," Athletics Kenya said in a statement.
"We are still working to unearth more details about her demise."
Keiyo North police commander Tom Makori said that Tirop's husband Emmanuel Rotich was a "man of interest" in the case and was the subject of a police hunt.
"He can tell us what happened," Makori said. "The suspect had made a call to Tirop's parents saying that he'd committed something wrong. So we believe he knows what happened."
On Saturday, compatriot and fellow long-distance athlete Hosea Mwok Macharinyang died by suicide, according to Kenyan athletics officials.
Macharinyang was found in his home in West Pokot, also in western Kenya.
"He was such a brilliant athlete, committed to the sport where he competed for Kenya for many years in both cross country and the 5,000m and 10,000m races," Jackson Pkemoi, the West Pokot representative of Athletics Kenya, said.
The 35-year-old made a record eight appearances, and won three consecutive titles for Kenya in the World Cross Country Championships from 2006 to 2008.
Kenya is the most successful nation at the event, having won 49 team and 27 individual titles.