BURBANK (CBSLA.com) – A Pasadena man pleaded guilty Thursday to murdering his live-in girlfriend, her 91-year-old father and a Good Samaritan who tried to come to her aid more than two years ago.

John Izeal Smith — who was set to go on trial next month in Burbank — pleaded guilty to two counts of first-degree murder for the July 12, 2014, shooting deaths of Maria Aguiar, 59, and her father, Luis Fernando Aguiar.

READ MORE: Man In His Mid 30s Fatally Shot In Carson

Smith also pleaded guilty to a count of second-degree murder for killing Jose Hernandez Iribe, 31, who rushed to Maria Aguiar’s aid at a home in the 1700 block of North Summit Avenue in Pasadena.

The 46-year-old defendant also admitted guilt to a count each of assault with an assault weapon on a peace officer and the attempted murder of Aguiar’s adult daughter.

The officer and Aguiar’s daughter were not hit by the gunfire.

Prosecutors had decided earlier not to seek the death penalty against Smith, who is now facing 181 years to life in state prison. He is set to be sentenced Feb. 1.

READ MORE: 2 Riverside Co. Sheriff's Deputies Recovering After Being Hit By Delivery Van; 2 Pedestrians Killed

Smith got into a domestic altercation with Maria Aguiar, grabbed an assault rifle and opened fire on her and her daughter as they ran from the house after the daughter confronted him, according to Deputy District Attorney Geoff Lewin.

Neighbors reported that Smith fired at least one more shot at Aguiar after she had fallen to the ground and was pleading for her life, the prosecutor said.

Smith went back inside the house, called 911, came outside again and fired more shots at multiple people, including a Pasadena police officer, Lewin said.

Iribe was struck by the gunfire after trying to come to the mortally wounded woman’s aid, according to the deputy district attorney.

Smith went back inside the home and killed Aguiar’s father, who lived with his daughter and Smith, while speaking to the 911 operator during the 38-minute call, Lewin said.

MORE NEWS: Due To Wind Concerns, Disneyland Vaccine Site To Be Closed Sunday

(©2016 CBS Local Media, a division of CBS Radio Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. Wire services contributed to this report.)