Police continue to make arrests in the aftermath of a months-long investigation into the illegal sale of oxycodone.

Town resident Daniel Renzulli, suspected by police of selling drugs, was placed under surveillance last month. They had arrested an Easton couple in May on drug charges for allegedly supplying Renzulli with narcotics after getting prescriptions refilled.

During their surveillance, police said Renzulli drove to Westport, where Irisel DeJesus worked. They allege he left 50 oxycodone tablets in DeJesus’ unlocked car. Renzulli was taken into custody at that time, and DeJesus turned herself in on a warrant July 10.

Renzulli, 46, of Sunnyridge Avenue, was charged with possession of narcotics, possession of narcotics with intent to sell, failure to keep narcotics in original container and conspiracy to possess narcotics. He was released on a promise to appear in state Superior Court and has not yet entered a plea. Renzulli’s next court date is Aug. 14.

DeJesus, 29, of East Main Street, Bridgeport, was charged with possession of narcotics, possession of narcotics with intent to sell and conspiracy to possess narcotics. She was released on a promise to appear July 21 at state Superior Court in Bridgeport .

Curtis Pistey, 55, and Joann Pistey, 54, of Adams Road in Easton, who police allege supplied Renzulli with the narcotics, have both entered pleas of not guilty and are awaiting trial. Their next court date is Aug. 6. Curtis Pistey is free on $250 bond, while Joann Pistey was released on a $100,000 bond.