A girl who refused to surrender her phone after texting in math class was flipped backward and tossed across the classroom floor by a sheriff's deputy, prompting a federal civil rights probe on Tuesday.

Videos of the confrontation between a white officer and a black teenager stirred such outrage that Sheriff Leon Lott called the FBI and Justice Department for help.

Lott suspended Senior Deputy Ben Fields without pay, and said what he did at Spring Valley High School in Columbia, South Carolina made him "want to throw up".