Six people were arrested Thursday morning in connection with a monthslong investigation into fentanyl trafficking in Penobscot County. Police executed a search warrant on Thursday morning at a Main Road residence in Enfield, where they seized more than a half pound of fentanyl and $1,000 in cash, according to the Maine Drug Enforcement Agency. The fentanyl was brought from out of state and sold throughout Penobscot County, the agency said Friday. The fentanyl was worth an estimated $40,000. As a result of the investigation, Tammy Lee, 61, who lived at the Main Road residence, was charged with aggravated trafficking of fentanyl. Christopher Campbell, 20, of Enfield; Madison Whitmore, 18, of Enfield; Naim Stewart, 32, of the Bronx, New York; Kenute Walker, 33, of the Bronx, New York; and Jquan Bailey, 33, of the Bronx, New York, also were charged with aggravated trafficking of fentanyl. They were taken to the Penobscot County Jail in Bangor, where bail was set at $10,000 for Lee, $50,000 for Campbell, $10,000 for Whitmore, $50,000 for Stewart and $50,000 for Walker.