A man who allegedly killed a woman after setting her on fire in a New York subway told police he “doesn’t know what happened,” NBC News reports.

Sebastian Zapeta-Calil, 33, is said to have used a lighter to start the fatal fire on Sunday, December 22nd. As the victim, who was not identified, was consumed in the fire, Zapeta-Calil allegedly began “fanning the flames with a lighter shirt,” a prosecutor alleged during his arraignment in Brooklyn on Tuesday, December 24.

Surveillance footage showed the victim sleeping on a stationary F train at the Coney Island-Stillwell Avenue station around 7:30 a.m. Zapeta-Calil, who was sitting across from her, allegedly set fire to her and the blanket she was lying under, CNN reported. citing a complaint from the Brooklyn District Attorney’s Office.

The prosecutor added that Zapeta-Calil told police after the incident that he “drinks a lot of alcohol” and “doesn’t know what happened.”

Zapeta-Calil and the victim were the only two in the car. He allegedly left the train, sat on a nearby bench and watched as the woman continued to burn, footage showed. Sources suggested she was unconscious the entire time, CNN reported.

A walker was spotted near the scene, suggesting the woman had difficulty getting around on her own. She was wearing multiple layers of clothing and officials believe that was the cause of the fire spreading. The woman is over 18 years old and a police officer has been informed The New York Times that she appeared to be homeless.

Zapeta-Calil was arrested after three students recognized his face when surveillance footage and images were released to the public. He was later found on a Herald Square train with a lighter in his pocket, NYPD Traffic Services Chief Joseph Gulotta said, according to CNN.

The New York coroner’s office classified the woman’s death as a homicide and determined that she died of “thermal injuries and smoke inhalation,” NBC News reports, citing court records.

When he appeared in court, he was charged with first- and second-degree murder and arson, according to court documents. He pleaded not guilty to all charges and was remanded in custody without bail.

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Zapeta-Calil, who appeared to be wearing the same hazmat suit he wore when he was escorted out of a local police station, is due back in court at 9 a.m. local time on Friday, December 27. NYPD previously told PEOPLE it was an “unlawfully present Guatemalan citizen” who was deported in 2018.

PEOPLE contacted the Brooklyn District Attorney’s Office and the Office of the Chief Medical Examiner in New York City.