Three teenage girls have been arrested in Chicago for allegedly beating an unidentified 15-year-old girl with disabilities in an incident captured in a video that went viral on social media.

Police spokesman Anthony Guglielmi told USA TODAY Thursday that two of the suspects are charged with aggravated battery, a felony. One was charged with mob action. The girls, who remain unidentified, are 13, 14 and 15.

One of the teens was arrested by police, said Guglielmi, while the other two turned themselves into police with their families. They are being charged as juveniles.

A video shows a group of girls swarming and striking the victim repeatedly as onlookers laugh. The girl, who then falls to the ground, cries for help. The clip was published Monday night by an unidentified Twitter user who claimed to be a friend of the victim. The tweet said that the girl has a "mental disability."

The Twitter user did not immediately respond to USA TODAY's request for comment.

Police did not confirm the motivation behind these attacks.

"There were some things going on that these young ladies wanted her to do that she didn't," said police superintendent Eddie Johnson in a news conference before trailing off. "We'll leave it at that for right now.

'Beyond disturbing':A teen girl was beaten as onlookers laughed, viral video shows

"Hate, bullying and bigotry are cancers of our society that do nothing but break and divide us," said Johnson.

Police spokesperson Jose Jara said Wednesday that the victim was missing for five days before she was reported missing by her family Tuesday. She was eventually found by a concerned individual and her father.

"At this point, it is believed that the victim was invited out by some girls who are so-called 'friends' who are eventually the offenders in these disgusting incidents," Jara said.

Johnson said Thursday that the police department was initially unaware of the video, and that the victim was originally reported as a missing persons incident.

Contributing: Associated Press

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