Angel Feliz killed Carmen Torres-Gonzalez in the hallway of the Mott Haven Houses, police said. View Full Caption DNAinfo/John Santore

MOTT HAVEN — A mentally ill man who thought his upstairs neighbors were spying on him hacked his neighbor's daughter to death with a machete in the hallway of their building in the Mott Haven Houses on Sunday afternoon, police said.

Angel Feliz, 26, attacked Carmen Torres-Gonzalez, 59, who was standing in the hallway of 383 E. 141st St., near Willis Avenue, about 4 p.m., an NYPD spokesman said.

Feliz thought that Torres-Gonzalez had been working in concert with his upstairs neighbors to spy on him, and police suspect that his mental health issues were behind the attack, according to the NYPD.

Torres-Gonzalez's screams of "help me!" in Spanish echoed up nearby staircases to neighbors above, they said.

Torres-Gonzalez, who was visiting her mother on the same floor where Feliz lives, was pronounced dead at the scene, police said.

One of her hands was completely sliced off, and the other was almost totally severed as well, according to the NYPD.

Feliz was arrested on charges of murder, manslaughter and criminal possession of a weapon, police said.

Investigators recovered a machete at the scene, police said.

Feliz has previous interactions with mental health facilities, sources said.

A neighbor said she recently saw him pacing back and forth in the lobby, mumbling to himself.