AUSTIN (KXAN) — Court documents revealed the suspect of an August hit-and-run crash that killed an elderly woman may have been on his cell phone as he was driving.

Weston Holtz, 18, turned himself in earlier this week and faces a charge of accident involving death, a second-degree felony, according the Travis County Jail records. Police believe Holtz hit and killed Sandra K. Neilsen, 70, with his car in the Circle C neighborhood the morning of Aug. 17.

KXAN has reached out to Holtz’s attorney. We will update this story once a response is received.

An arrest affidavit for Holtz said a neighbor provided officers with video footage that shows the roadway just before the intersection of Way Lane and South Bay Lane where the crash happened. At 8:35 a.m. the video showed a black car with the passenger-side window down.

The affidavit said, “the driver is seen holding an object in his right hand that appears to be a cell phone.” Police further wrote the driver is “looking at the object as if a person would be looking at a cell phone while driving.” The sound of the crash can then be heard over the video’s audio.

It’s illegal to text and drive in the state of Texas, but cell phone laws can go beyond that depending on the city. The City of Austin, for example, has an ordinance that prohibits the use of all electronic handheld devices while driving a vehicle or riding a bicycle. That went into effect in 2015.

Data from the Texas Department of Transportation said last year, nearly one in five crashes on roads in the state were caused by distracted driving in which over 400 people died, and nearly 3,000 were seriously hurt. Distracted driving encompasses more than just cell phone use; it can include eating and drinking, putting on makeup, shaving and reading, among other things.

The affidavit also revealed officers used cell phone location data to track Holtz to California, where he and his car were located. Police also spoke with Holtz’s place of work, where the manager said Holtz texted him to say he was moving to California, because he got into a jewelry school.