An accused killer is set to be arraigned next month on charges that he killed his 65-year-old mother and 73-year-old stepfather in a bloody baseball-bat attack at the the victims’ Hacienda Heights home and also attacked his younger brother, according to the Los Angeles County District Attorney’s Office.

Nelson Garibay, 44, is charged with two counts of murder for the Jan. 11 killings of Ima Garibay and Mario Flores-Romero, along with the attempted murder of his 37-year-old brother.

Garibay allegedly beat his mother and stepfather after yelling was heard in the back yard, where his stepfather’s body was found, according to the District Attorney’s Office. His mother’s body was found in the garage. There was no indication of what may have precipitated a violent argument, or what the interaction was between the alleged killer and his victims.

Garibay’s brother — who was also attacked with a baseball bat — survived, authorities said.

“The facts in this case are truly disturbing and we will ensure that there is accountability for these senseless killings,” District Attorney George Gascon said in an announcement Tuesday. “We ask that if anyone has information that can be helpful to the investigation and prosecution of this case, please contact the Los Angeles County Sheriff’s Department.”

Sheriff’s deputies were called to the home in the 14400 block of Marwood Street, near Janette Street, about 12:30 p.m. They they were met outside by Garibay’s brother, who said he had been attacked by the defendant.

Garibay was taken into custody last Thursday in the San Diego County community of Otay Mesa and is being held without bail, jail records show.

He’s set to be arraigned Feb. 11 at the Pomona courthouse and could face up to 57 years to life in state prison if convicted as charged, according to the District Attorney’s Office.

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