DALLAS -- Federal officials say a motorist's use of marijuana and a sedative led to a collision with a church bus that killed 13 people on the bus.

The National Transportation Safety Board said in a report released Tuesday that toxicology tests on Jack Dillon Young, who survived the March 2017 crash, found the drugs in his blood stream. According to the report, Young said he had taken twice the prescribed dosage of the sedative before the wreck.

The report also said the minibus lacked seatbelts that might have averted some fatalities.

The bus from First Baptist Church of New Braunfels was returning from a senior retreat when the crash happened.

 In May 2018, Young plead no contest to a variety of different felony charges. He could receive up to 270 years when he is sentenced next month.

The Associated Press contributed to this report.

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