Lebanon — Working with the Hartford Police Department and other law enforcement agencies, Lebanon police on Wednesday said they had arrested nine Upper Valley residents and cited them into court on charges that they sold heroin in the community.

One of the defendants also allegedly sold fentanyl, an painkiller that is 50 to 100 times more potent than morphine, and a 10th resident was charged with selling Suboxone, according to a news release announcing the arrests on Wednesday.

The Upper Valley defendants range in age from 19 to 40 and live in the towns of Orford, Hartford, Plainfield, Enfield and Grafton, as well as the city of Lebanon.

Two others who live outside of the Upper Valley were also arrested on heroin-related charges.

Lebanon Police Chief Richard Mello, who took the reins of the department in December, said he hopes the drug arrests send a message to dealers that such behavior will not be tolerated.

“Others who are going to engage in drug sales … will be held accountable,” Mello said. “The people who are actively involved in sales at any given time could be killing people and that is a concern.”

The “vast majority” of the arrests were not connected to one another, Mello said.

“There is not a conspiracy between them all,” Mello said.

The investigation into drug activity began in the late spring, and officers used a variety of techniques to observe the alleged dealers in the act. Among them were undercover investigators executing drug buys, something the New Hampshire Drug Task Force specializes in, Mello said.

Mello and other area police chiefs said they understand the issue of addiction and hope the arrests lead people to treatment.

“These arrests provide important support to those struggling to recover from a heroin addiction as they reduce the opportunity for an addict to resupply, while also serving as a warning to others contemplating the illicit trade,” Hartford Police Chief Phil Kasten said via email. “We are all united in advancing the health and safety of our communities.”

Hartford police aided Lebanon with the drug sweep, along with members of the Drug Task Force, Probation and Parole and Manchester and Littleton, N.H., police departments.

The Lebanon Police Department has also issued arrest warrants for three other Upper Valley individuals, each of whom faces a heroin sale charge, Mello said.

One woman, whose picture was in the middle of the news release, faces solely a marijuana possession charge. She was included in the release because she was part of an investigation into one of the alleged heroin dealers, Mello said.

Depending on their criminal background, some of the individuals will be arraigned this week in Lebanon District Court.

Others were summoned to appear in court at a later date.

Jordan Cuddemi can be reached at jcuddemi@vnews.com.