Police apprehended a man accused of setting a woman on fire as she appeared to be sleeping aboard a New York City subway train early Sunday morning, resulting in her death.

The chilling incident unfolded around 7:30 a.m. at the Coney Island-Stillwell Avenue station in Brooklyn. The victim, whose identity remains unknown, sat motionless on a stationary F train when a man calmly approached her and ignited her clothing with a lighter, according to the NYPD. Authorities noted that there was no interaction between the two prior to the attack, and they believe the pair were strangers.

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As flames engulfed the woman, the suspect exited the train car, just as officers patrolling the station arrived at the scene.

"What they encountered was a horrifying sight—a person fully engulfed in flames inside the train car," NYPD Commissioner Jessica Tisch said during a press briefing.

Shocking cellphone footage shared on social media captured a man in a gray hoodie, resembling the suspect later arrested, sitting on a bench near the burning victim. When questioned, police stated that responding officers initially had no reason to suspect the individual on the bench was the attacker, as their priority was extinguishing the blaze and aiding the woman.

Emergency responders pronounced the victim dead at the scene after officers used fire extinguishers to douse the flames.

Later that day, police arrested a suspect riding the subway, although his identity has not yet been disclosed. Investigators continue to work on identifying the victim and determining the motive behind this heinous act.

New York City's subway system, which facilitates approximately 4 million rides daily, is generally considered safe, with violent crimes being relatively uncommon. However, this year has seen an increase in subway homicides, with nine reported as of November, compared to five during the same period last year.

The attack comes on the heels of another high-profile subway case earlier this month, where Daniel Penny was acquitted of criminally negligent homicide in the death of Jordan Neely. Neely, a homeless man and former Michael Jackson impersonator, was restrained in a fatal chokehold by Penny after shouting at passengers on a train.

As the investigation into Sunday’s tragic incident unfolds, it leaves a city reeling and searching for answers to yet another senseless act of violence.