DETROIT WP)—Two peace offi cers Whom 19-year-old Dominick Piccone threatened to kill three years ago strapped on their guns today and started a search for him as a suspect in the revenge slay ing of two Oakland county farm ers. The search was led by Detective Clare R. Davis of Highland Park, a Detroit suburb, and Deputy Sher iff Ted Gunn of Oakland county, who arrested Piccone in Novem ber, 1938, on a felonious assault charge on which he was paroled from the state prison only two weeks ago. At the time of the arrest, auth orities said, Piccone threatened to “get” the two officers and Miss Johanna Johnson, a negro school teacher whom he was accused of attempting to assault. She since has moved to Chicago. The slayings occurred last night at the homes of the two victims. Authorities feared the slayer had kidnaped, or killed, a third Oak land county farmer in his fiight. The murder victims were Cassius Barber, 71, on whose farm Pievone worked for eight months in 1937 and 1938, as a parolee from the Wayne county juvenile court, and his cousin, Romaine C. Potter, 75, a neighbor, Roy Thorpe, 56, a friend and neighbor, was missing. Police said he had been driving in the vicinity at about the time of the killings. Piccone was named as a suspect by, Mrs. Elizabeth Murphy, Bar ber’s 90-year-old mother-in-law, who was in the Barber home at the time of the killing. She said she heard a shot in the kitchen and then Piccone and a companion forced her to lead them to a bed room which they ransacked. A pis tol was missing after they de parted. The slaying of Potter was discov ered three hours later when friends stopped at his home to tell him about the killing of Barber. Authorities said both killings oc curred at about the same time and that both men were slain with .22 calibre bullets of the same type They said they assumed that the killings were in revenge for some fancied injustice during the time Piccone worked on the Barber farm.