Story highlights "This is as bad as it gets," police official says

Jerome Isaac came to police station "reeking of gasoline," police say

The suspect says the victim owed him $2,000

The victim is identified as Deloris Gillespie, 73

A 47-year-old man was arrested Sunday in the death of a 73-year-old woman who was set on fire in the elevator of her Brooklyn apartment building, telling police the woman owed him $2,000, New York police said.

Jerome Isaac faces charges of first-degree and second-degree murder, along with arson, police said in a statement.

The victim was identified as Deloris Gillespie. Isaac also lives in Brooklyn, but does not live at the address where the incident took place, police said in a statement.

Isaac told police Gillespie owed him $2,000 for work he claims he did for her, said NYPD Deputy Commissioner Paul Browne. He turned himself in to police overnight or early Sunday morning, he said.

Neighbors said the woman was returning home to her fifth-floor apartment in Prospect Heights after a grocery store trip Saturday.

A preliminary investigation showed the man was standing outside the elevator on the fifth floor and attacked the woman as she was attempting to exit, authorities said. The incident was caught on surveillance cameras inside and outside the elevator, and police have the videotapes, Browne said.

Authorities believe Isaac initially sprayed the woman with a flammable liquid, presumably gasoline, and continued to spray her as he followed her back into the elevator, Browne said. The woman was first sprayed in the face, he said.

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Then, using "one of those long lighters that you would use for a grill, he lit a Molotov cocktail and used the burning leg on top of that to ignite her body," Browne said.

The suspect stepped out of the elevator, threw the Molotov cocktail inside, then returned again to spray more liquid on the woman as she burned, he said.

"This is as bad as it gets," Browne told CNN's Don Lemon.

Authorities responding to a 911 call of a fire found the woman's body inside the elevator. She was pronounced dead at the scene, according to the police statement.

Residents told CNN affiliate WCBS they heard screams and saw smoke -- and realized a woman was on fire inside the elevator.

"Myself and someone from the sixth floor went down knocking to get people out. Knocking on doors telling people 'There's a fire, get out, get out," a resident named John told the station. He did not want to give his last name.

Neighbor Carmen Martinez told the station the victim had lived in the building since the 1980s.

"She used to give toys and gifts to kids all the time," Martinez told the station.

"From everything we hear ... she was just this sweet 73-year-old woman," Browne said.

Photos that police released of the attacker show a man dressed in dark blue clothes, white gloves, with a dust mask on his head and carrying a container on his back. The photos were released during the search for a suspect, Browne said.

Isaac lived about 10 minutes away from Gillespie's apartment building, Brown said. After the incident, he apparently returned home and ignited the door to his own apartment, he said.

He was concerned he had burned himself in the second incident, although no one else was injured, Browne said. He then hid out on a rooftop for a while and fell asleep, later going into a police station "reeking of gasoline" and telling officers he was responsible for a fire. During questioning, Browne said, he implicated himself in Gillespie's death.

It was not clear whether Isaac had retained an attorney.