An official toxicology report confirmed the narcotic was in Jeff Rice's blood, dispelling initial suspicions the father-of-two known for his work on the U.S. show "The Amazing Race," had been poisoned by attackers.

Rice, who was found slumped over a table bleeding through the nose and mouth, died of asphyxiation, a post mortem showed. Drug users who fall unconscious risk inhaling vomit.

"Rice ... used cocaine which had lethal additives and that's what killed him," Uganda police spokesperson Asuman Mugenyi told Reuters.

Brad Nathanson, a private investigator and friend of Rice, said he had been shown the toxicology report by police and there was no evidence of "foul play" in Rice's death.

"In fact it was as a result of buying bad drugs, cocaine to be specific ... it was a bad concoction," Nathanson told reporters.

"I have read the toxicology report ... it shows that there were small traces of cocaine in their blood and urine," he said, adding he had travelled to Uganda as a friend of the Rice family following rumours he had been poisoned, and not for payment.

Rice's assistant, identified by police as Kathryne Fuller, was found unconscious at the same time Rice's body was discovered on February 18 at the Serena hotel in the capital, Kampala. She is now conscious but paralysed down the right hand side of her body.

Ugandan police said on Saturday they had arrested a man who confessed selling drugs to the pair who had been in the east African country working on a documentary.

Fuller's father said he was "disappointed, sad" but would support his daughter, a South African.

"We all do stupid things in life. Unfortunately this is a large mistake but we can't exactly crucify her," Stewart Fuller said.

Rice and Fuller were believed to have voluntarily consumed the drugs, meaning Fuller could be prosecuted under Uganda's drug laws. Drug use can carry a jail term in Uganda.

(Reporting by Elias Biryabarema; Editing by Richard Lough)

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