Police announced this afternoon they arrested 30-year-old Nikhom Thephakaysone on suspicion of gunning down 20-year-old Justin Valdez on Muni Monday night.
Sgt. Danielle Newman says Valdez was riding the M line at about 9:50 p.m. through the Ingleside Heights neighborhood when the bus stopped at the intersection of Randolph and Bright streets. As he exited the bus, Valdez was shot in the back of the head.
Police say he and the suspect did not know each other, and it appeared to be a random and unprovoked attack.
Last night, police released video surveillance showing the suspect on the train right before the shooting. Afterward his picture was released, Thephakaysone, a San Francisco resident, was taken into custody outside of his residence in the Oceanview District.
Thephakaysone was booked into San Francisco County Jail where he's been charged with homicide. Here's footage of the suspect prior to the shooting:
Police are holding a press conference later today to provide more details about the case.
Valdez graduated from Garden Grove High School in Southern California where he was described as a "persistently positive kid." He was also an accomplished swimmer and polo player, according to the Examiner.