The oft-repeated “if you see something, say something” mantra appears to have worked out in the case of an alleged attack at a Metro Red Line station that was observed and recorded by a bystander.Witness Lake Cunningham recorded a video of an alleged assault on Tuesday morning at about 1 a.m. at the Hollywood and Vine station. The video depicts a younger white man punching an older black man in the head on the station platform. Cunningham also claimed that the younger man kicked the older man in the face, though it is not seen on the video. Though police had been called at the time of the alleged attack, all involved parties had departed the station by the time they arrived.Cunningham’s video was widely distributed via social media and various news outlets, and authorities say they subsequently received numerous tips, CBS Los Angeles reports. One of those tips involved a 32-year-old Culver City man named James A. Hanson, who police say confessed to being the younger man in the video. Hanson was arrested Thursday afternoon at about 1 p.m. He is currently being held in lieu of a $50,000 bail, according to Fox 11.”Hanson has admitted to his role in the assault and has been booked at the sheriff’s Century Regional Detention Facility,” L.A. County Sheriff’s Office Deputy Ramon Montenegro said.The victim in Cunningham’s video also came forward following news reports about the incident and was treated for injuries suffered during the assault.