Murdered tech mogul Bob Lee was killed in a mugging during a quick visit to San Francisco, friends say.
Bob Lee, 43, whose latest position was at cryptocurrency company MobileCoin, was found in the early hours of Tuesday in the exclusive residential area of Rincon Hill and was rushed to hospital but died of his injuries.
His dad has paid a heartbreaking tribute to his slain son who "worked harder than anyone and was the smartest person I have ever known".