AUBURN – Three men and a woman were arrested on cocaine trafficking charges late Wednesday after investigators spent a day keeping the suspects under surveillance.

Another man was arrested by federal agents at a camp in Raymond, charged with trafficking crack cocaine in the Twin Cities.

The arrests on Wednesday bring the total number of suspects charged with trafficking crack and powdered cocaine here to 24 in the last eight days.

Acting on information from a confidential informant Wednesday afternoon, local, state and federal investigators put four of the suspects under surveillance in Lewiston and Auburn.

Wednesday night, police stopped two of the suspects on Minot Avenue in Auburn. There they arrested Lisa Ritchie-Rains, 40, of Auburn, and William Perkins, 24, of Oxford. Each was charged with attempted trafficking in cocaine.

Around the same time, two other suspects were stopped by police on Empire Road in Poland. Steven Proctor, 44, of Auburn, and Omer Levesque, 50, of Lewiston, were charged with trafficking in cocaine.

Those arrests involved local police, federal and state drug agents as well as investigators from the Central Maine Violent Crime Task Force.

After the four suspects were taken to the Androscoggin County Jail in Auburn, agents from the CMVCTF went searching for Philip Perkins, 47, of Otisfield.

Police had been searching for Perkins since last week when 13 people were arrested on federal warrants for trafficking in crack in the Lewiston-Auburn area.

Perkins eluded arrest until Wednesday night when federal agents found him at a camp in Raymond, officials said. He was arrested and taken to the Cumberland County Jail in Portland to await a hearing in U.S. District Court.

Police say more arrests are likely as the result of ongoing investigations into the local cocaine trade. The Maine Drug Enforcement Agency has been working with federal agents as well as local police departments.

On June 3, investigators swept through Lewiston and Auburn and surrounding areas. By the end of the day, 19 people were arrested and charged with trafficking in cocaine. All but six of them face federal drug charges.