On Saturday, a 34-year-old man was killed in the parking lot of Memorial Park, according to the Upland Police Department. Investigators say the victim had been involved in a prior altercation with the suspect, Pete Renteria, who later returned to target the victim.
Renteria was arrested shortly after that deadly shooting.
Investigators had been searching for the 29-year-old for months in connection to the deaths of three of his family members.
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Back in January, the victims - 68-year-old Sonia Ramirez, 66-year-old George Ramirez and 43-year-old David Ramirez - were all found shot to death in a home on Ramona Place in Ontario.
Renteria, who is now in custody, had been identified as the primary suspect in the killings.
The victim in Saturday's incident has not been identified.