Los Altos police have released a sketch of a man who allegedly hit an 89-year-old man in the head and left him unconscious on the ground, police said.
The suspect is described as a white male, possibly 20 to 40 years of age, about six feet tall, 180 pounds, with a thin to average build.
The assault happened on Sept. 16 sometime in the late morning or early afternoon, police said.
The victim suffered life-threatening head injuries and was left on the railroad tracks in the area of Foothill Expressway and Highway 280, police said.
Investigators detained and questioned a person of interest who possibly knew the victim, police said.
The victim has since been released from the hospital to recover at home, police said.