ATLANTA >> The 10-line report, written on wide-ruled notebook paper by an elementary school student in Chattanooga, Tenn., arrived Nov. 16.

“The bus driver drives fast,” the Woodmore Elementary School student wrote. The driver of Bus No. 366, the child added, drove so fast that it felt “like the bus is going to flip over.” And when a student stood in the aisle, the child wrote, the driver “stops the bus and he makes people hit their head.”

Five days later, the bus driver, Johnthony K. Walker, driving 37 children home from Woodmore, strayed from his route and crashed, leaving six children dead in one of the country’s deadliest school bus wrecks in recent years.

The crash, for which Walker has been charged with vehicular homicide, is being investigated by the National Transportation Safety Board and the Chattanooga police. Records released today by the Hamilton County Department of Education showed that Walker’s behavior was a frequent worry this semester.

In a statement, the school district acknowledged that its records contained “many emails of complaint and concern.” Walker, 24, is not a district employee and instead worked for Durham School Services, a contractor based in Illinois that says it carries more than 1 million schoolchildren each day.

Complaints about Walker flowed into — and from — Woodmore. In September, a parent, Jasmine Mateen, wrote to a teacher that the bus driver was cursing students and slamming on his brakes, “making them hit they heads and fall out” of their seats.

“He did intentional stuff to them kids on the bus all the time,” Mateen said in an interview Tuesday, a day after one of her 6-year-old daughters was killed in the wreck. Two of Mateen’s other children were injured.

More than a month after Mateen’s letter, one of Woodmore’s behavioral specialists investigated when Walker complained about disrespectful students. According to the records released, the specialist, Carlis Shackelford, said that Walker “stated he did not care about the students and proceeded to tell the students he did not care about them.” An administrator spoke with Walker soon afterward.

About the time that school officials wrote emails expressing alarm about how often Walker was making referrals for behavioral issues aboard his bus, they also documented concerns about his driving.

“On Tuesday, 11/8, the driver, in my opinion, was driving way too fast when he pulled out of our school,” Woodmore’s principal, Brenda Adamson-Cothran, wrote in an email on Nov. 11. “It was not as bad as yesterday, but still not optimal.”

On Nov. 16, records show, the principal warned in an email that six students had reported that Walker “was swerving and purposely trying to cause them to fall today.”

A Chattanooga police officer, in an arrest affidavit that was released Tuesday, said that Walker had been driving “at a high rate of speed, well above the posted speed limit of 30 mph” on Monday afternoon. The police said Wednesday that Walker, who had been involved in a minor bus crash in September, was not under the influence of alcohol or drugs at the time of Monday’s wreck.

Durham has not responded to questions about its hiring practices or Walker’s tenure in his part-time job. On Wednesday, the company’s chief executive, David A. Duke, apologized for the wreck and said Durham would “cooperate fully” with investigators.

The school district said Friday that it “does not have any records of any accidents or disciplinary records pertaining to Durham employees.” A spokeswoman for Durham, Molly Hart, said the company had no comment about the documents the school district released.

© 2016 The New York Times Company