Watch: Mom of school bus crash victims says she told school about bus driver in August

Monday afternoon, tragedy struck when a school bus crash claimed the lives of five children in Chattanooga, Tennessee. The bus driver, Johnthony Walker, has since been arrested and charged with five counts of vehicular homicide, reckless endangerment, and reckless driving.

Jasmine Mateen, mother of one of the crash victims and two other children on the bus, told NBC News she called and wrote letters to the school and the board of education beginning in August, shortly after school started.

"I've been calling, complaining about the bus driver since August," Mateen said.

Mateen told reporters she called the school itself, the board of education, and the bus driver's employer, Durham School Services. She alleged the bus driver was slamming on his brakes on purpose so the kids would hit their heads.

She said she even wrote a letter to the bus driver himself, which the principal allegedly read aloud to the driver in front of the students.

"She read it to the bus driver, out loud, in front of all the kids. After she got done with the letter, he said, 'so? I'd do it again.'"

Mateen also told reporters the bus driver involved in the accident was drinking every day on the bus and cursing at the children.  She added he was also always speeding.

Watch her interview with NBC News below: