CTA fatal stabbing: New details emerge in train attack, video recorded by suspect

CHICAGO - A man charged with murder in a fatal stabbing on a CTA Blue Line train recorded the entire attack and its aftermath on his cellphone, according to newly released court documents.

What we know:

Prosecutors said Demetrius Thurman, 40, stabbed 37-year-old Dominique Pollion while he was sleeping on a Blue Line train early Saturday morning.

According to court records, Pollion had been asleep in a train car for about an hour and had no interaction with Thurman before the stabbing. Prosecutors said they did not know each other.

At around 2:17 a.m., Thurman allegedly walked up behind Pollion, began recording with his phone and with a knife with a bright orange handle, stabbed Pollion once in the chest near his heart and a second time in the abdomen.

Pollion reportedly woke up, screamed and tried to back away down the aisle before collapsing. Thurman then crossed into another train shortly before the train pulled into the Clark/Lake station, according to prosecutors.

Pollion was taken to Northwestern Memorial Hospital, where he died.

Prosecutors said the entire incident and aftermath were captured on CTA surveillance video and on Thurman’s phone.

Court documents state that immediately after the stabbing, Thurman turned his phone's camera on himself, "capturing his face directly in the video."

A short time later, once the train arrived at the Clark/Lake station and an unknown rider alerted security officers on the platform that something had happened, Thurman allegedly turned the camera on himself again while recording from outside the train car and said, "somebody got his ass."

He then left the CTA station, prosecutors said.

Detectives then gathered still photos from CTA surveillance video that showed Thurman's face and submitted them to the state's facial recognition program, which provided authorities with the suspect's name. They then distributed a "seeking to identify" bulletin and a Chicago police officer who encountered Thurman a few days earlier recognized the suspect.

According to that officer, they found Thurman sleeping on a Blue Line train and Thurman provided the officer with his driver's license. The encounter was captured on the officer's body-worn camera.

Thurman was arrested Sunday in the West Loop at 210 S. Canal Street. He appeared to be wearing the same clothes that he wore during the stabbing, according to prosecutors. A phone in his possession was also obtained and on it, police reportedly found the recordings of the stabbing. Prosecutors said detectives also discovered photos of other sleeping passengers on the train.

Police then contacted Thurman's cousin, who identified him as the suspect seen on surveillance video.

Additionally, prosecutors said Thurman admitted to stabbing Pollion. He was charged with one felony count of first-degree murder.

The backstory:

According to court records, Thurman has a criminal past, including getting supervision for both disorderly conduct in 2014 and a DUI in 2017, and, most recently, a 2023 traffic arrest in which he eventually pleaded guilty and also got supervision.

What's next:

Thurman, of the Park Manor neighborhood, had a detention hearing on Tuesday. He is due back in court on Jan. 20.

CTA crime

Dig deeper:

Thurman was the second man charged with murder this week in connection with a CTA attack in the Loop.

Pedro Villareal, 34, was charged in a shooting on a CTA Pink Line train last month that left one rider dead and another wounded.

The shooting happened around 1:22 a.m. Dec. 23, 2025, on a train near Wells and Washington streets in the Loop.

Police said a 23-year-old man and a 44-year-old man were on the train when an argument broke out with the suspect, later identified as Villarreal, who was armed with a knife.

At some point, one of the victims pulled out a gun, but police say Villarreal "gained control" of the firearm and started shooting.

The 44-year-old man, identified as Raymond S. Harrison Jr. of Chicago, was shot in the abdomen and taken to Northwestern Hospital, where he died. The 23-year-old was shot in the wrist and survived.

He was charged with one count of murder, one count of attempted murder, multiple weapons-related felonies and a CTA trespassing citation.

Under the spotlight

Big picture view:

Crime on the CTA has drawn federal scrutiny, stemming from a November incident when a man set a woman on fire aboard a train downtown.

On Dec. 19, federal transit officials ordered the agency to submit a new, tougher safety plan within 90 days or risk losing a quarter of its federal operating funds, citing failures to meaningfully address crime on the system.

The Federal Transit Administration said CTA is out of compliance with a special safety directive issued earlier that month that requires measurable reductions in transit worker and customer assaults, along with a surge in security staffing. 

If CTA does not submit a revised plan and obtain federal approval, the FTA said it will withhold 25 percent of the funds the agency receives under federal law. The notice served as a formal warning under federal transit safety statutes and regulations.

The FTA said CTA’s plan failed to set monthly reduction targets for assaults over the next six months, as required, and did not propose significant increases in security or law enforcement presence on buses and trains.

"I'll say it plainly: CTA, city, and state leaders are failing transit riders and operators," Federal Transit Administrator Marc Molinaro said in a statement at the time. "This 'plan' fails to measurably reduce incidents of assaults and improve overall safety on buses and trains. If people’s safety is at risk, so are federal funds. CTA must act to save lives and improve safety."

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