A man is facing murder and arson charges in New York City for allegedly setting a woman on fire inside a subway train and then watching her die after she was engulfed in flames, police said Monday.

The suspect, identified by police as Sebastian Zapeta, was taken into custody hours after the woman died on Sunday morning.

Zapeta, 33, is a Guatemalan citizen who entered the U.S. illegally after he had been previously removed in 2018, said Jeff Carter, a spokesman for U.S. Immigration and Customs Enforcement.

Surveillance video showed the suspect approach the woman, who was sitting motionless and may have been sleeping, on a stationary F train at the Coney Island-Stillwell Avenue subway station in Brooklyn and set her clothing on fire, police said.

The woman's clothing "“became fully engulfed in a matter of seconds,” said Jessica Tisch, the New York City police commissioner, while the suspect remained at the scene, watching her burn from a bench on the subway platform as police and a transit worker extinguished the flames.

The woman was pronounced dead at the scene. Police have not yet released her identity.

Tisch called the incident “one of the most depraved crimes one person could possibly commit against another human being.”

Police arrested Zapeta later Sunday, riding the same subway line, after getting a tip from a group of high school students who recognized images of the suspect that were circulated by police.

It is unclear when and where Zapeta reentered the U.S. after being removed about six years ago.

In a statement, Brooklyn District Attorney Eric Gonzalez said, “The depravity of this horrific crime is beyond comprehension, and my office is committed to bringing the perpetrator to justice."

“This gruesome and senseless act of violence against a vulnerable woman will be met with the most serious consequences,” he said.

It was unclear if Zapeta has an attorney or when he would be arraigned.

A Brooklyn address for Zapeta released by police matches a service center for Samaritan Daytop Village, which provides housing and substance abuse support. The organization did not immediately respond to a request for comment.

New York Gov. Kathy Hochul this year has sent New York National Guard members to the city’s subway system to help police conduct random searches of riders’ bags for weapons following a series of high-profile crimes on city trains. Hochul recently deployed additional members to help patrol during the holiday season.

About a year ago, Hochul supported funding to install video cameras on every train car in the New York subway system, said Michael Kemper, chief security officer for the Metropolitan Transportation Authority. He and other officials on Sunday credited the cameras with helping to track down the suspect so quickly.