SAN DIMAS – A 19-year-old man has been arrested for allegedly killing his father, who was found on Mount Baldy Road in the San Gabriel Mountains, authorities said Sunday. The attack was reported at 3:28 p.m. Saturday, according to the Los Angeles County Sheriff’s Department. When deputies arrived at the site near Stoddard Canyon Falls, they found a man suffering from trauma to his upper body. He was pronounced dead at the scene.