US authorities are investigating whether a the arrest of a student who refused to leave her high school maths class violated federal civil rights laws.
In footage posted on social media, a police officer can be seen flipping the girl backward in her desk and tossing her across the classroom floor.
Federal help was sought by the local sheriff, who placed Senior Deputy Ben Fields on leave after the confrontation at Spring Valley High School in South Carolina.
Officials have confirmed that Fields is white and the students are black, but told The Associated Press in an email to "keep in mind this is not a race issue".
The sheriff's department said no one was hurt during the confrontation, which was captured on mobile phones by several students.
One student said it all started when the girl refused her teacher's request to hand over her phone during class.
Video shows Fields standing over the girl, asking her to stand up.
The girl remains seated and the officer wraps a forearm around her neck. The desk then flips and the girl is slammed backward onto the floor, where the officer tosses her toward the front of the classroom and handcuffs her.
A second student who verbally objected to the girl's treatment was also arrested.
Both girls were charged with disturbing schools and released to their parents.
Their names were not released, but the second student, Niya Kenny, told WLTX-TV that Fields' use of force shocked her.
Her mother, Doris Kenny, said she's proud her daughter was "brave enough to speak out against what was going on".
The district's Black Parents Association denied that the issue was unrelated to race, saying the video "revealed what many African-American parents have experienced in this district for a very long time".
The officer has been accused of excessive force and racial bias before, but has prevailed in court so far.
Trial is set for January in the case of an expelled student who claims Fields targeted black students and falsely accused him of being a gang member in 2013.
In another case, a federal jury sided with Fields after a black couple accused him of excessive force and battery during a noise complaint arrest in 2005.
A third lawsuit, dismissed in 2009, involved a woman who accused him of battery and violating her rights during a 2006 arrest.
