Local police commander Patrick Wambani reported that Bett, aged 28, was killed after his car struck a bump and veered off the road near Nandi County in Kenya’s high-altitude North Rift region.
Bett had only just returned home from the African Senior Championships in Nigeria on Monday.
Following reports of the accident, Kenya’s Athletics governing body confirmed Bett’s death on Twitter, sending condolences to his family and the entire athletics fellowship.
Kenya’s deputy president, Williams Ruto also expressed his sympathy over Bett’s death, calling it “a big loss to his family, friends, Kenya and the global athletics fraternity,” on Twitter.
The International Athletics Foundation also said it was “deeply saddened and shocked to hear,” of Bett’s passing in a post on Twitter.
Bett made history at the World Championships in Beijing in 2015 after taking gold in the 400m hurdles, the first ever for a Kenyan.
He also won two bronze medals at the 2014 African championships in Marrakech, Morocco in the 400 hurdles and 4×400-meter relay.
Bett did not make the podium at the African Championships in Nigeria.
His twin, Aron Koech, also an international hurdler, took the honors as part of the Kenyan team that won gold in 4×400m event, adding to Kenya’s final tally of 11 golds, two more than South Africa and hosts Nigeria.