NASHUA - Two men were arrested on Saturday after one of them allegedly sold oxycodone to the other, a drug transaction that was witnessed by a concerned citizen.

Police say William Castro, 37, of 36 Allds St., allegedly sold a number of pills to Michael LeLacheur, 21, of 37 Schaefer Circle, Hudson.

LeLacheur was still in possession of the drugs when police made contact with him, and following a search warrant additional narcotics were allegedly found in Castro's vehicle, according to police.

Castro is charged with sale of a narcotic drug, possession of a narcotic drug and two counts of possession of a narcotic drug with the intent to distribute. He was being held on $75,000 cash bail pending an arraignment on Monday at the 9th Circuit District Court in Nashua.

LeLacheur was charged with possession of a narcotic drug, and was being held on $5,000 cash or surety bail pending an arraignment Jan. 15.