NASHUA - City police, who conducted their second drug sweep in as many weeks, say they anticipate even more arrests on top of the eight individuals recently charged with selling narcotics to undercover officers.

"It is always ongoing. I actually do have more warrants out there," Lt. David Bailey said Tuesday after confirming the weekend arrests of two men and two women accused of selling oxycodone and heroin to authorities. The weekend prior, local police arrested four other individuals on similar drug charges, all of them separate investigations over the past few months.

"There are some people we are still looking for," acknowledged Bailey. "It's hard because you arrest one person, and someone else picks up the business. Unfortunately, that is what happens."

But for now, four alleged drug dealers are behind bars. Those arrested include: Daniel Davis, 23, of 8 Arlington St., Nashua; Patti Amadon, 42, of 343 Forest Road, Wilton; Candido Vazquez-Matos, 18, of 4 Hammond Court, Nashua; and Kerri Fisette, 18, of 10 Mayflower Drive, Litchfield.

Davis allegedly sold oxycodone to city police on three separate occasions in October. He is facing three counts of the sale of a narcotic drug, and one charge of resisting arrest. According to court documents, Davis was previously convicted of possessing a controlled drug in 2008 in Nashua. He was being held on $100,000 cash bail.

Amadon allegedly sold heroin to city police on three separate occasions in October. She is facing three counts of the sale of a narcotic drug and was being held on $50,000 cash or surety bail.

Vazquez-Matos and Fisette allegedly sold oxycodone to police on three occasions this past summer, including incidents in Hudson and Nashua. In addition to three counts of the sale of a narcotic drug, they are also each facing three counts of conspiracy to the sale of a narcotic. They were being held on $100,000 cash bail.

All four were arraigned Monday at the 9th Circuit Court, Nashua District Division. Police affidavits detailing their crimes were sealed at the courthouse Tuesday.

Their arrests follow four separate arrests earlier this month on unrelated heroin, cocaine and marijuana charges. Arrested in the first drug sweep were: Karl Meacham, 31, of Nashua; Tasha Lemar, 28, of Nashua; Joshua Rosario, 19, of Nashua; and Dennis Plouffe, 49, of Nashua.

Bailey encourages citizens to call the Narcotics Hotline at 594-3597 with any information concerning illegal drug activity in Nashua.