It happened on June 28 near Lubican Street and Merced Avenue.
Police say the victim was walking past Manuel Alejandro Valenzuela's car, when Valenzuela jumped out and attacked him for no reason.
Valenzuela was arrested on suspicion of elder abuse.
Anyone else who may have been attacked by Valenzuela is asked to contact Baldwin Park police at (626)960-1955, ext. 414.