A man has been charged with stabbing a CTA passenger to death while the victim was sleeping on a Blue Line train over the weekend in the Loop.

Cook County prosecutors said 40-year-old Demetrius Thurman used his phone to record video of the crime early Saturday morning. His public defender argued he suffers from mental health problems.

Thurman has been charged with first-degree murder in the death of 37-year-old Dominique Pollion. The attack was not only recorded by CTA surveillance cameras on the train, but by Thurman himself, according to prosecutors.

At his Thurman's first court appearance on Tuesday, prosecutors said Pollion had been sleeping on a Blue Line train for about an hour when Thurman entered the same train car around 2:15 a.m. on Saturday, holding a phone in one hand and a knife in the other.

Thurman walked up to Pollion from behind while he was still sleeping, and began to record video on his phone before stabbing Pollion in the chest and abdomen.

Awakened by the stabbing, Pollion screamed and backed away from Thurman, who kept moving toward the victim before turning his camera into selfie mode, before Pollion collapsed.

Prosecutors said Thurman then moved to another train car, and when the train stopped at the Clark/Lake station, a passenger alerted security officers on the platform, who found Pollion inside the train.

Pollion was wearing so many layers of clothing security officers couldn't immediately tell he'd been stabbed.

As security officers were checking on Pollion, Thurman was recording from outside the train and turned the camera back on himself to say, "somebody got his a**" before leaving the station.

Paramedics took Pollion to Northwestern Memorial Hospital, where he was pronounced dead.

After running surveillance video footage of Thurman through the Illinois Secretary of State's facial recognition program, detectives identified Thurman as the killer.

Thurman was arrested the next day at 210 S. Canal St., while still wearing the same clothes he had on at the time of the stabbing. He also still had his cell phone on him, and after obtaining a search warrant, detectives recovered the video recording he'd made of the attack.

It was one of the latest violent crimes on the CTA.

On Dec. 23, one man was killed and another was wounded in a shooting on a Pink Line train. Police and prosecutors said 34-year-old Pedro Villarreal got into an argument with a 44-year-old man on a Pink Line train, and tried to stab him, when a good Samaritan tried to come to his aid, pulled out a gun, and hit Villareal in the head.

When the Good Samaritan dropped the gun, Villarreal picked it up, shot the good Samaritan in the wrist, and then shot the 44-year-old man in the chest. That man, identified as Raymond S. Harrison, was pronounced dead at the scene. The good Samaritan was treated at Northwestern Memorial Hospital.

Villarreal had previously been found guilty on battery and assault, once for swinging a knife at someone.

Meantime, police were still looking for the person who stabbed and seriously injured a CTA passenger on the Red Line at 69th street early Sunday.

Despite those recent crimes, CTA data shows violent crimes across the system – counting all CTA property, including buses, trains, stations, lots, tracks, and garages – dropped 6% in 2025 compared to 2024.

It's too early to tell how 2026 crime on the CTA compares to 2025.

Nonetheless, CTA faces a mid-March deadline to meet the Trump administration's demand for an improved safety plan or risk losing $50 million in federal funding.

In December, CTA said dozens more Chicago police officers and security guards would be deployed along the bus and train system.

But the additional officers were not enough for the Federal Transit Administration, which rejected that safety plan in a letter to acting CTA President Nora Leehrsen in a letter on Dec. 19, and gave the agency 90 more days to provide an enhanced security plan.