Anthony Velasquez is charged with three counts of murder. He is accused of gunning down Jesse Avalos in February of 2014, Eduardo Robles in July of 2015 and Amanda "Nikki" Lopez in April of 2018.
Manuel Velasquez, Anthony's father, is charged with one count of murder in connection to Robles' death and being an accessary in the other two.
The arrests came after an $80,000 reward was offered in the case and investigators received multiple tips.
A preliminary hearing is set for Jan. 25, where both sides will present their evidence in the case.
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Anthony Velasquez remains in custody with his bail set at $6 million. Manuel Velasquez's bail is set at just over $2 million.
Avalos was found shot to death on Feb. 11, 2014, at about 3:25 a.m. in the 4800 block of East Telegraph Road, sheriff's Capt. Joe Mendoza said at an August news conference.
About four hours before he was killed, Avalos had received a call from an acquaintance asking him to go to the location to jump-start a vehicle, and he went there to help, Mendoza said. Avalos was found shot to death while seated in the driver's seat of his SUV. Two suspects were seen leaving the area.
Robles was fatally shot on July 6, 2015, at about 7:30 p.m. after he got into a fight with a suspect in the driveway of a residence in the 4300 block of Eagle Street, according to investigators. About 15 to 20 people were at the location at the time, but none provided information leading to the arrest of the suspect.
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Lopez was fatally shot on April 22, 2018, at about 2:40 a.m., as she slept in a tent near a homeless encampment in the 200 block of Fetterly Avenue. The scene was located in front of the East Los Angeles field office of Los Angeles County Supervisor Hilda Solis.
Security video showed the gunman, who wore a mask, exiting a light-colored Chrysler PT Cruiser and firing into the tent, authorities said. The suspect had gone to the encampment looking for Lopez. After the shooting, the gunman ran to the PT Cruiser, which was driven by another man, and it sped off.
However, once he was inside the vehicle, the gunman took off his mask, and witnesses saw his face, Mendoza said. Composite drawings were later circulated of the two men, as was security video from the crime scene.
According to Mendoza, ballistics evidence showed that the same gun was used in the first two killings. Investigators believe the driver accompanied the gunman in the second and third killings.
Homicide detectives said Anthony Velasquez knew each of the victims in some capacity.
City News Service contributed to this report.