Police haven't said what led up to the fight that ended with a girl's head getting slammed onto the ground repeatedly.
CNN  — 

A Missouri girl was critically injured in a fight captured on video near Hazelwood East High School, the St. Louis County Police Department said.

Video of Friday’s altercation has since been shared by thousands of people online. It shows a girl getting thrown to the ground and punched in the head by another teen girl, who slams her head onto a concrete sidewalk multiple times.

Other teens were fighting around the injured girl as she lay on the ground shaking, the video shows.

It’s not clear what led to the fight, and police are not publicly identifying those involved. But police confirmed the viral video is connected to the investigation, according to police spokesperson Vera Clay.

The assault victim was in critical condition after the fight, St. Louis County police said.

Officers responded to a call at 2:32 p.m. Friday for a “fight in progress near the intersection of Norgate Drive and Claudine Drive,” St. Louis County police said in a statement Monday.

“Responding officers located a juvenile female suffering a severe head injury. The victim was transported to an area hospital where she remains in critical condition,” police said.

A 15-year-old female suspect was arrested Saturday and was being held by St. Louis County Family Court on assault charges, police said.

No updates have been made in the case as of Thursday, a police spokesperson said.

St. Louis County Prosecuting Attorney Wesley Bell called the video “sickening” and “difficult to watch” in a social media post Sunday.

Bell said the juvenile court system – not his office – has jurisdiction over the case, “We pray the victim makes a full recovery,” the prosecutor added. “This is just heartbreaking.”

Missouri Attorney General Andrew Bailey called the incident “evil” and a “complete disregard for human life.”

“I am praying for the victim. The criminal should be charged and tried as an adult,” Bailey posted on X. “If the victim dies, that offense should rise to a homicide.”

It was not immediately clear whether those involved in the fight were students at Hazelwood East High School, less than half a mile away from the scene of the fight.

But the Hazelwood School District said it is “a tragedy anytime children are hurt.”

“Bullying and fighting in the community is an issue for which we all need to take ownership and work towards a resolution for the sake of our children,” the district said in a Facebook post Saturday.

A crisis team will help provide emotional support to those in need, the school district said.

“Please be kind and respectful of the families involved during this difficult time and pledge to help work toward the betterment of our entire community,” the district said.

CNN’s Holly Yan and Chris Boyette contributed to this report.