The Riverside County Department of Animal Services said Thursday Richard Mazon spotted the 2-month-old terrier mix chasing after a car that had just pulled from the shoulder of eastbound California 60, the Los Angeles Times reported Friday.
Officials said Mazon pulled over and rescued the puppy from oncoming traffic near the Pedley Road exit in Jurupa Valley.
"This man is a hero," Officer Mark Visyak said. "If not for his quick thinking, the dog likely would have continued running onto the highway."
Visyak said the dog will be available for adoption June 5 if no owners come forward.