18-year-old arrested after confessing to killing father and brother in Fresno in May, police say

FRESNO, Calif. (KFSN) -- An 18-year-old man has been arrested in a twist to a shooting investigation in west central Fresno.

Back on May 17, Fresno police found 53-year-old Patrick Cotter dead from a gunshot wound at a mobile home off of McKinley and Pleasant Avenues, inside the Villa Fresno Mobile Home Park.

Police also found 15-year-old Brian Cotter suffering from a gunshot wound inside the home.

Brian was hospitalized and died a few days after.

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Authorities interviewed 18-year-old Robert Cotter, who was also in the home at the time of the incident. Initially, Robert said that his brother shot their dad and then shot himself.

The investigation continued and it was determined that Robert's statements were inconsistent with the evidence found.

On Friday, police arrested Robert for the murder of his father and brother. Investigators say Robert revealed his plan to kill his father and brother to them and admitted to the murders.

Robert was booked into the Fresno County Jail on two counts or murder.