Police say they've arrested and charged a 21-year-old man for fatally attacking and sexually abusing an elderly woman walking in her Queens neighborhood.

Maria Fuertes, 92, was walking around the corner from where she lived on 127th Street near Liberty Avenue in Richmond Hill shortly after midnight on Monday when a man came up from behind her and knocked her down. Police say the man attacked Fuertes for several minutes, and she suffered injuries on her neck and in her private areas from the attack.

"Ms. Fuertes was a defenseless 92-year-old woman minding her own business walking down the street when she was brutally attacked," Chief of Detectives Rodney Harrison said at a press conference announcing the arrest.

Police apprehended the 21-year-old suspect Thursday night.

By Friday afternoon, officers identified the man as Reeaz Khan, of Queens, who was charged with murder and sex abuse for the attack.

It remains unclear whether Khan knew the woman.

Investigators have obtained security camera video that partially documented the attack.

"There was some sort of physical contact between the two—between Ms. Fuertes and this unknown male—causing them to both fall to the ground where they landed behind a parked car," NYPD Deputy Chief Joseph Kenny said. "The perpetrator and the victim were out of view for approximately four to five minutes when the subject suddenly reappears and runs northbound on 127th Street."

Fuertes remained on the ground, where medical personnel found her injured and disoriented lying in the snow, he said. She was pronounced dead at Jamaica Hospital about two-and-a-half hours later.

Khan has a prior criminal history, though police officials declined to disclose further details. It is believed that this particular attack was an isolated incident, and during an interview with investigators, he "put himself at the scene." The NYPD is working with the Queens District Attorney Melinda Katz on the case.

The woman was a "fixture in the neighborhood of Richmond Hill," said Kenny. "She was known on Liberty Avenue. She took strolls in the evening quite often."

"Homicide. I really find that hard to believe," the woman's son, Ray Fuertes, told the Daily News. "Why would anybody do this to her? This is ridiculously crazy...I never thought I'd face anything like this. I can barely talk about it."

This article has been updated to indicate the suspect was arrested and charged.