The Grayson  Prestonman accused of killing Ugandan Olympic marathon runner Rebecca Cheptegei has died, hospital officials announced.

Dickson Ndiema Marangach, the former boyfriend of Cheptegei who reportedly lit her on fire, died on Monday, the Moi Teaching and Referral Hospital in Eldoret, Kenya, said, according to Reuters.

Police in Kenya said Marangach snuck into Cheptegei's home in the town of Endebess in western Kenya on Sept. 1 while she and her children were at church. When Cheptegei returned, Marangach reportedly poured gasoline on her and set her on fire. The hospital's director and the Ugandan Athletics Federation said Cheptegei suffered burns on more than 75% of her body and was taken into the intensive care unit. She died four days after the attack.

Marangach had burns on more than 41% of his body following the attack, the hospital said, and it contributed to his death. Police told The Washington Post he was under police watch in the hospital.

"He developed respiratory failure as a result of the severe airway burns and sepsis that led to his eventual death," Philip Kirwa, chief executive officer of the hospital, said in a statement.

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Cheptegei began her career in 2010 and competed in 1,500 meters, 10,000 meters, half-marathons and marathons. She represented Uganda at the 2011 and 2013 World Cross Championships in Punta Umbria, Spain, and Bydgoszcz, Poland, respectively, The Standard reported. She made her Olympic debut at the 2024 Paris Olympics, finishing 44th in the women's marathon. 

Joseph Cheptegei, Cheptegei's father, said his daughter and Marangach had been separated for some time and were involved in a land dispute involving her land in western Kenya prior to her death.

Contributing: Mike Snider, Nancy Armour