UVALDE, Texas -- ​The National Transportation Safety Board will meet this week in Washington D.C. to determine the probable cause of the Uvalde bus crash that killed 13 people in March of 2017.

• 21-year-old truck driver and one passenger of the bus were the only survivors
• Driver could receive up to 270 years in prison when he is sentenced next month

Earlier this month, The National Transportation Safety Board released an 800-page document giving information about the crash. All of the findings in that document are fact-based and did not include an analysis about how the crashed happened.

MORE | Details released in Uvalde bus crash that claimed 12 lives

On Tuesday, the NTSB will present their findings and recommendations on the probable cause of the crash for their board's approval. The crash happened when a pickup truck crossed the center lane dividing U.S. 83 into a bus carrying senior citizens. All of the passengers were church members on their way back home from a retreat. The 21-year-old truck driver and one passenger of the bus were the only survivors. According to investigators, Jack Young confessed to texting while driving along with being under the influence of prescription drugs. The Texas Department of Safety said troopers also found marijuana in his truck.

According to the NTSB, before the crash witnesses in the car following the pickup recorded a nearly 15-minute long video showing the pickup crossing over the northbound lane to the shoulder more than 30 times. Officials also say the video showed the truck crossing over the middle lane nearly 20 times at one point driving on the wrong side of the road.

The witnesses called law enforcement, who were on their way at the time of the crash. 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.

CONTINUING COVERAGE:

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