A man was allegedly pickpocketed, then beaten by a group of teenagers on a train Monday in Chicago, Illinois.

Surveillance footage taken from inside the red line train showed a female suspect in a green jacket standing near the 68-year-old man as he slept on the train, according to Fox News.

Reporter Matt Finn tweeted the disturbing video on Friday.

At one point, the suspect appeared to reach down and take something out of the victim’s pocket and gestured to another woman wearing a pink jacket to be quiet.

A few moments later, the woman moved out of view and appeared to sit down next to the sleeping man. When he awoke, she grabbed him and dragged him onto the floor, hitting him several times.

Later in the video, several teenagers surrounded the victim and one in a light blue jacket grabbed the bar above the man’s head and proceeded to kick him as others joined in.

Several bystanders failed to help the victim during the alleged beating, the report noted.

When he made it to the Argyle station, train workers helped the man off and authorities were then able to interview him about the incident.

He was later taken to a nearby hospital and treated for his injuries.

“Police documents indicate he suffered blunt force trauma,” the report said.

At the Argyle station, police also detained and interviewed a group of teenagers. However, they were sent home not long after.

The Chicago Police Department (CPD) said the investigation was ongoing but no arrests were made because the victim “was unable to identify his attacker(s) due to his injuries.”

CPD officials met with Chicago Transit Authority (CTA) officials on Friday to discuss how to curb the recent uptick in violent crimes perpetrated on the red and blue lines, according to ABC 7.

“What we wanna do is put more of a presence not only on the platforms but riding the trains themselves,” said CPD Interim Superintendent Charlie Beck.

“It is safe for public transportation compared to some other major cities but it certainly is not safe enough,” he noted.

CTA’s Anti-Harassment Campaign stated that unwanted behavior would not be tolerated and urged passengers to say something if they or someone else was being victimized.

“It’s important for everyone riding one of our buses or trains to know that we take harassment seriously – one incident is one too many,” the website concluded.