A woman is currently hospitalized after being set on fire on the Chicago train system, according to police.

At around 9.25pm on Monday, a 26-year-old woman was riding the Chicago Transit Authority system’s Blue Line near the Clark/Lake station when she got into an argument with an approximately 45-year-old man.

According to Chicago police, the argument escalated physically and the man poured an unknown fluid over the woman’s body before igniting it.

The train then came to a stop and the suspect fled the scene. Police added that the woman stumbled out of the train and fell on to the ground. The flames were extinguished before police arrived.

The woman was then transferred to Stroger hospital, where she is being treated for severe burns and remains in critical condition.

Speaking to Fox 32, one witness said: “Just seeing her lying on the ground and she was kind of hyperventilating and in a lot of pain. You could tell she was in really bad shape. All the medics were down there and there was a big turnout as far as responders and so forth.”

Another witness told NBC Chicago, “I just saw a lady that was laying on the ground, and they were trying to give her CPR,” before adding: “And she looked like she was in an awful lot of pain.”

Trains resumed service at around 1.30am and operated normally as of Tuesday morning. A person of interest in the attack was taken into custody, police said later in the day.

Monday’s incident follows a similar one that occurred in New York City late last year when a 57-year-old woman was set on fire and killed in a subway car.

The woman, identified as Debrina Kawam of Toms River, New Jersey, was unhoused and had been sleeping on the train when she was attacked.

The suspect was identified as 33-year-old Sebastián Zapeta, who was later charged with murder and arson.