A former Tennessee school bus driver was found guilty Thursday of six counts of criminally negligent homicide in a crash that killed six elementary school students, according to the Chattanooga Times Free Press.

In November 2016, Johnthony Walker, who was 24 at the time, lost control of a bus with 37 Woodmore Elementary School students on board. He swerved, struck a telephone pole and a tree.

Walker was arrested and charged with 34 crimes, including six counts of vehicular homicide.

The jury deliberated about six hours before reaching a verdict of guilty on all counts -- including a charge of using a portable electronic device by a school bus driver.

During Walker's trial this week, a video from the bus was played in court that appeared to show Walker with his cellphone in hand as children boarded the vehicle. According to ABC News, prosecutor Crystle Carrion argued, "It all could have been avoided if Johnthony Walker had slowed down below the speed limit and stayed off his phone."

When he took the stand in his defense Wednesday, Walker told the court he wasn’t on his phone while driving and said he wasn’t speeding despite being accused of driving 20 mph over the limit. His defense attorneys argued another car caused Walker to swerve.

Joe Warren, a Chattanooga police officer who reconstructed the scene, testified Tuesday that no evidence suggested the second vehicle was in Walker's lane of travel. If it had been, Warren said, there would've been a head-on collision based on tire marks.

Authorities ruled out drugs and alcohol as explanations for the crash.

Walker is set for sentencing on April 24.