The FBI and the U.S. Department of Justice launched a civil rights investigation Tuesday into the actions of Officer Ben Fields -- a South Carolina sheriff’s deputy who was seen in a video Monday thrashing an African-American girl in a classroom at Spring Valley High School in Columbia -- to determine if any federal laws were broken. Fields, the school's resource officer, also arrested the student who reportedly refused to acknowledge her teacher’s demand to put away her cellphone.

The video, showing the female student being thrashed and slammed to the ground on Monday, went viral on social media and the South Carolina chapter of the National Association for the Advancement of Colored People (NAACP) called for Fields to be charged with assault, Reuters reported. Fields also arrested another female student who had spoken up against him.

Fields -- who had earlier been named as a defendant in two other lawsuits claiming racial bias and use of excessive force -- has been suspended without pay since the incident came to light. Both the girls were arrested because they caused disturbance in the classroom.

“This young student may have broken school rules, but there is nothing that indicates she broke any criminal laws or was a physical threat to anyone at the level that would require this officer to treat her like a violent criminal. This is yet another example of the misuse of force and the exceedingly disproportionate contact of resource officers with young minority students,” NAACP President and CEO Cornell William Brooks said in a statement Monday.

“The NAACP applauds federal officials on their announcement of a full investigation and demands that this officer be terminated and never again employed in a position where he has any law enforcement encounter responsibility with the public,” Brooks added.

Richland County Sheriff Leon Lott, who had asked the FBI and the DoJ to investigate the incident at Spring Valley High School amid widespread outrage, said he did not know if race played any role. Lt. Curtis Wilson also said that people need to "keep in mind this is not a race issue," the Associated Press (AP) reported.

However, Lonnie Randolph Jr., the president of South Carolina's NAACP, countered it by saying, according to the AP: "Race is indeed a factor."

"To be thrown out of her seat as she was thrown, and dumped on the floor ... I don't ever recall a female student who is not of color [being treated this way]. It doesn't affect white students," Randolph added.

Todd Rutherford, the lawyer for the unidentified girl who was beaten, told ABC News that his client was “brutalized” by Fields and her hand was in a cast. He also criticized law enforcement agencies for not condemning Fields’ actions that led to the girl's hospitalization Monday night.

"She is hurt and literally, this is someone who is physically in pain because of what she endured, as she literally flew across the classroom," Rutherford told ABC News, adding: "They [the sheriff] simply stood behind their officer. They are going to wait 48 to 72 hours to determine whether he did anything wrong, when the rest of the world can determine instantly that something is wrong, that you should never treat a child that like, that a classroom is not a wrestling mat."

Rutherford made the comments after the Richland County sheriff said a new video of the incident has emerged that shows the girl retaliating to the officer’s use of force, though the sheriff added that the investigation will focus on Fields.

Besides trending on social media, the video has also gained political attention with Democratic presidential candidate Hillary Clinton tweeting about the incident Monday.

The other girl arrested Monday was identified as Niya Kenny, 18, by WLTX-TV. She said she was just standing up for her classmate.

“I couldn't believe this was happening," Kenny reportedly said, adding: "I had never seen nothing like that in my life, a man use that much force on a little girl. A big man, like 300 pounds of full muscle. I was like 'no way, no way.' You can't do nothing like that to a little girl. I'm talking about she's like 5'6"."

Tony Robinson Jr., who recorded the video on Monday, told WLTX-TV: "When I saw what was about to happen my immediate first thing to think is let me get this on camera. ... I've never seen anything so nasty looking, so sick to the point that you know, other students are turning away, don't know what to do, and are just scared for their lives."

Fields joined the sheriff’s department in 2004 and became a school resource officer four years later in 2008. He was also assigned to Lonnie B. Nelson Elementary School. A newsletter from the sheriff's department last November reportedly said that Fields had “proven to be an exceptional role model to the students he serves and protects.”

However, according to a lawsuit filed against him in 2013 by Ashton Reese, a former student at Spring Valley High, Fields “unfairly and recklessly targets African-American students with allegations of gang membership and criminal gang activity.” In 2007, another lawsuit was filed against Fields by a couple -- Carlos Martin and his wife, Tashiana Martin -- for violating their civil rights and using excessive force against Carlos.