KNOXVILLE, Tenn. — An autopsy on a school bus driver involved in a fatal accident here in December shows that he died later of natural causes, but was on several prescription medications at the time of his death in June, Knoxville News Sentinel reports.

James Davenport drove his bus into another school bus, killing two students and a teacher’s aide. He was injured, but survived the crash. However, he was found dead of natural causes at his home on June 2. He was driving while distracted at the time of the accident, and authorities have said he was sending and receiving text messages, according to the newspaper.

Autopsy results show that Davenport had morphine and oxycodone in his bloodstream, which he was taking under a physician’s prescription, the newspaper reports. A medical examiner wrote that the toxicology report at the time of his death shows his blood had “therapeutic concentrations” of several prescription medications.Toxicology reports from the crash showed that he did not have drugs in his system at the time, according to Knoxville News Sentinel.

Davenport said he took the pain pills as needed for a back injury, and his phone showed numerous calendar appointments at a pain clinic, according to the newspaper. The autopsy also said that multiple health issues, including hypertension, obstructive pulmonary disease and morbid obesity, contributed to Davenport’s death, Knoxville News Sentinel reports.

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