The mother of Pedro Vargas, who was fatally shot by police after he killed six people in the Miami suburb of Hialeah, had requested psychiatric assistance for her son in a 911 call before his shooting spree, investigators said Thursday.

Vargas called 911 a few hours before he began the massacre and told the dispatcher that he felt threatened and that someone was following him.

During the July 27 call, which lasted 12 minutes and was conducted in Spanish, the dispatcher asked to speak with Vargas' mother, 83-year-old Esperanza Patterson.

Patterson said her son was very "disturbed" and that she wanted to get him an appointment with a psychiatrist.

The dispatcher decided to send the police to the apartment, but Patterson told her to cancel that order because her son had left the home.

Vargas went to the office of attorney Angel Castillo, who had interviewed him under oath the week before for a legal case in which he was involved, Miami's El Nuevo Herald newspaper said Thursday.

Vargas did not find the lawyer at his office, which saved the man's life, according to authorities, who believe that he intended to kill Castillo.

In the 911 call, Vargas told the dispatcher that a lawyer named Castillo was performing witchcraft on him, and some of his relatives later told investigators that he was afraid of losing all his money as a result of the court case.

After returning to his apartment, Vargas set fire to $10,000 in cash and tried to burn his laptop computer.

It was the smoke from those fires that alerted a neighbor couple, who came to Vargas' apartment but were met by him with gunfire there and killed.

After that, Vargas knocked down the door of another nearby apartment and killed its three occupants.

Police believe that the sixth victim - a man who was standing across the street - died when a stray bullet fired by Vargas during the shootings inside the building struck him. EFE