New York City police arrested a man suspected of setting fire to a woman on the subway in Brooklyn who died from the incident, authorities said, calling it “one of the most depraved crimes” a person could commit.

The man “calmly walked up to the victim” on the F train in Brooklyn and set her ablaze on Sunday morning, New York City Police Commissioner Jessica Tisch told a press conference.

“The suspect used what we believe to be a lighter to ignite the victim’s clothing, which became fully engulfed in a matter of seconds,” she said, adding that police rushed to the scene and the fire was put out with an extinguisher.

“Unfortunately it was too late and the victim was pronounced dead on the scene.”

Reviewing footage from body cameras, the police got a clear image of the suspect as he “had stayed on the scene, and was seated on a bench on the platform just outside the train car,” Tisch said.

After disseminating his image to the public, the police received a tip-off from three high schoolers and arrested the suspect at a Manhattan station.

“I want to thank the young people who called 911 to help. They saw something, they said something, and they did something,” Tisch said.

Neither the suspect nor victim was identified, though NYPD’s Joseph Gulotta said: “There was no interaction between the two when the incident happened.”

“We don’t believe they knew each other,” he said during the press conference.

He added that the man immigrated from Guatemala to the United States in 2018.