A California man has pleaded guilty to several murder charges for killing four people and three dogs inside a home in November 2024.

Janvi Maquindang, 21, Matthew Montebello, 21, Edwin Garcia, 24, and Christine Aca-ac, 25, were fatally shot inside a Lancaster, Calif., home on Nov. 16, 2024, according to the Los Angeles County District Attorney’s Office.

Miguel Diego Sandoval, 21, pleaded guilty last week to carrying out the massacre and setting the home on fire, the DA’s office said in a statement.

The investigation revealed Sandoval, then 19, was “angered” after breaking up with his ex-boyfriend, who was Aca-ac and Maquindang’s brother, and carried out the shooting as “revenge.” Sandoval lay in wait outside the home until the victims went to bed. He then entered the home and carried out a shooting rampage, the DA’s office said in their statement last week.

Sandoval then set the home on fire and fled.

A 16-year-old girl who called 911 was rescued from a locked room in the house after officers responded to the scene.

Sandoval also fatally shot three dogs inside the house, police previously said.

The four deceased victims were honored fondly by their families in separate GoFundMes set up for them at the time.

Aca-ac was the legal guardian to her four younger siblings, read a fundraiser set up for her and Maquindang.

“[She] was a loving sister and a funny, vibrant, and deeply caring friend,” it said, adding she was “a source of strength for everyone around her.”

Maquindang was a high-school valedictorian “already making his mark on the world,” read his tribute in the fundraiser. “Janvi was an incredible listener, always there when someone needed to talk things through. His kindness, intelligence, and sense of humor left a lasting impact on everyone who knew him.”

Edwin, who was engaged to Aca-ac, was a “gentle soul” and “pillar of joy and happiness at every gathering,” his family said in the GoFundMe set up for him, adding that he aspired to pursue a career as a educator both in academics and music. “Fer wanted to be a leader and teacher for future generations and present ones as well.”

Montebello, who was Maquindang’s partner, “always was eager to learn, and whenever he set his mind on learning something or picking up a skill, he would relentlessly obsess over it for months at a time until he either mastered it, or at least got familiar with it enough to get bored and move on to his next ‘phase,’” his brother said in a GoFundMe

“While I myself always wanted to be a role model to him and for him to look up to me, many times I’ve found myself looking up to him both literally(he was taller than me) and figuratively,” Andrew Montebello said, adding, “Nothing will ever come close to the bond I had with my little brothe.”

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Sandoval pleaded guilty on Thursday, Aug. 13 to four counts of first-degree murder with the special circumstance allegations of multiple murders and murder by means of lying in wait; one count of attempted murder, first-degree residential burglary and arson of an inhabited structure or property; three felony counts of animal cruelty; and two counts of child abuse under circumstances or conditions likely to cause great bodily injury or death, according to the DA’s office.

He is set to be sentenced in November to life in prison without parole.

If you are experiencing domestic violence, call the National Domestic Violence Hotline at 1-800-799-7233, or go to thehotline.org. All calls are toll-free and confidential. The hotline is available 24/7 in more than 170 languages.