The fire department said at least 23 children were injured and taken to the hospital. The bus was carrying roughly 35 children from Woodmore Elementary School.

Chattanooga bus crash: reports of complaints about driver

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Police have said the bus crash sent 23 people to area hospitals and 35 schoolchildren were on the bus Monday afternoon.

Chattanooga police said five children died at the scene. They confirmed a sixth death Wednesday.

Johnthony Walker, 24, was arrested and charged with five counts of vehicular homicide, reckless endangerment and reckless driving, according to WTVC.

Chattanooga police say speed is being investigated "very, very strongly" as a factor in the crash.

"It is a complicated crime scene that covers a significant area. I can't tell you if there were any issues (with road conditions). There were none that jumped out. Right now it appears that one contributing factor may be speed but that is part of an active, ongoing investigation," CPD Chief Fred Fletcher said.

The bus driver is being questioned and is cooperating, according to WTVC.

The bus was the only vehicle involved in the crash.

Photos released by the Chattanooga Fire Department show the bus split in half by a tree. They said several patients had to be extricated from the bus.

WSB-TV reported that, in a Wednesday news conference, police said that a toxicology report found no trace of drugs or alcohol in the driver's system at the time of the crash. Police are still speaking to witnesses and children on the bus for more information. They are also looking a video from multiple angles before, during and after the crash.

The students on board ranged from kindergarten through fifth grade.

The Associated Press reported that concerns about Walker's driving were raised by students, according to records released by the school district Friday.

"The bus driver was doing sharp turns and he made me fly over to the next seat. We need seat belts," a student wrote. 

"It feels like the bus is going to flip over. ... He makes people go seat to seat back and forth, when someone is in the aisle he stops the bus and he makes people hit their heads," another student wrote.

Carlis Shackelford, a school behavior specialist sat on the bus Nov. 2 after Walker complained about students' behavior on the bus and that they were not listening to him.

"The driver was now visibly upset and continued on by saying that he had another job and driving this bus was just a part-time job for him," Shackelford wrote. "Driver stated that he could just leave him at the school. He then stated 'or I can just leave the student on the bus and I will get off the bus and leave the school.'"

Benjamin Coulter, transportation supervisor for the district, said the district was "addressing the issue with the driver."

– The Associated Press contributed to this report.

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