Eight people are facing drug trafficking charges following a monthslong investigation into the sale of fentanyl and other illegal drugs in the Waterville region and also Midcoast Maine, state officials announced Tuesday.

Most of the eight are from Waterville and Winslow and were arrested over the last week as part of a sweeping investigation into drug trafficking in Androscoggin, Kennebec and Waldo counties, the state Department of Public Safety said in a news release.

More than 150 grams of crack cocaine and another 60 grams of fentanyl were seized as a result of the investigation, authorities said. The street value of the drugs was estimated at $20,000.

The eight were arrested following extensive surveillance of the suspects, vehicle traffic stops, the undercover purchase of various drugs from the suspects and the use of several search warrants, officials said in the release.

Those arrested, and the charges they face, are:

• Stephon Davis, 27, of Waterville, two counts of aggravated trafficking of fentanyl and one count of aggravated trafficking of cocaine.

• Baron Thompson, 45, of Winslow, trafficking in fentanyl and trafficking in cocaine.

• Meloney Moody, 48, of Winslow, five charges of aggravated trafficking in cocaine, four charges of aggravated trafficking in fentanyl and two counts of aggravated trafficking in methamphetamine.

• Dawn Wilbur, 51, of Winslow, a charge of trafficking in cocaine.

• Charles Hinton, 45, of Savannah, Georgia, a charge of trafficking in cocaine and felony possession of fentanyl.

• Dominique Kirk, 25, of Lewiston, two charges of aggravated trafficking in fentanyl and two counts of aggravated trafficking in cocaine.

• Allen James, 41, of Waterville, aggravated trafficking in cocaine.

• Alivia Gordon, 25, of Jackson, trafficking in cocaine.

Davis was arrested before the others, back in June, authorities said. Kirk was transported to the Androscoggin County Jail in Auburn while the others were taken to the Kennebec County Correctional Facility in Augusta.

Officials noted that the investigation is ongoing and more arrests are possible.

The investigation was coordinated by the Maine Drug Enforcement Agency along with Maine State Police, sheriff’s offices in Franklin and Kennebec counties, and police in Augusta, Farmington, Waterville and Winslow.

This story will be updated.