Richland County Sheriff Leon Lott speaks during a press conference in Columbia, S.C. (AP Photo/Alex Sanz)

A South Carolina sheriff's deputy who flipped a student backward in her desk and tossed her across the floor for refusing to leave math class could learn as soon as Wednesday whether he will be fired.

Richland County Sheriff Leon Lott said once his agency's internal investigation is completed, he will make a decision about whether to keep Senior Deputy Ben Fields on the force.

The videos of the confrontation between a white officer and black girl stirred such outrage that Lott called the FBI and Justice Department for help. A criminal investigation is underway, but the probe generally takes more time.

(© 2015 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed)