Robert Arthur Calderon, 27, of Altadena, was shot and killed in Pasadena on December 18, 2015. Officers responding to multiple calls about gunfire found him at about 10:45 p.m. on the grassy strip between the street and the sidewalk in the 600 block of North Mentor Avenue; he was pronounced dead at 11:02 p.m., having sustained multiple gunshot wounds to his torso. Investigators recovered seven 9-millimeter shell casings at the scene. It is unclear whether he was struck while crossing the street or after exiting a vehicle, and no witnesses have provided details.

The following day a memorial at Kings Villages apartments where Calderon visited friends was disrupted by gunfire; two types of casings were found and a woman in her 20s was wounded in the stomach and expected to survive, but she has not cooperated with police. Detectives say Calderon had associations with some local gang members but found no conclusive evidence that the killing was gang-related. The Los Angeles County Board of Supervisors reinstated a $20,000 reward for information leading to an arrest and conviction.

Anyone who knew Calderon or who was in the area that night is asked to come forward with information.