An outbreak of drug overdoses in the Fargo-Moorhead area, with at least three confirmed deaths, has prompted law enforcement to sound the alarm Sunday about the spreading danger.

At a hastily called news conference, police in Fargo joined their colleagues in Moorhead and other nearby communities to say that they fear the overdoses are being fueled by heroin laced with even more potent narcotics.

The lacing with painkillers such as fentanyl and morphine is making the ingesting of heroin "even more dangerous than it already is," said Fargo Police Chief David Todd.

Moorhead Police Chief David Ebinger said there is a "strong chance there's something more deadly than what we've been contending with up to this point."

Four people were arrested Sunday morning at the Residence Inn in Fargo on suspicion of illicit drug use and possession. Authorities believe the four are connected to the death of a man on Saturday. His identity has yet to be released.

At least two and possibly all of the suspects have connections to the Twin Cities, police said.

Fargo Police Lt. Shannon Ruziska, in charge of narcotics investigations, said police believe "a lot" of the opiates coming into the Fargo-Moorhead area are "channeling through" the Twin Cities beforehand.

This laced batch of drugs suspected to be circulating can even be harmful when touched, let alone ingested, Todd said.

Fargo police said there have been seven incidents dating to late February, with four of them involving opiates. Heroin is among that class of drug, along with oxycodone and morphine.

The Forum of Fargo newspaper reported over the weekend that six recovering addicts were abruptly discharged from a state-funded residential treatment program in late February, a decision that prompted some former staffers to claim the move was an ethics breach.

A day after leaving the nonprofit Sharehouse facility, the newspaper continued, one of the patients was found dead from an apparent overdose in a Moorhead motel on Feb. 26. The Forum said 42-year-old Shawn R. Hansen was considered mentally unstable and deemed at high risk to relapse, according to the laid-off employees.

Addressing the newspaper report, Todd said "that's certainly going to be a topic of discussion" among city leaders, but "that's probably not my area of expertise."

Late last month, Beltrami County authorities said they received four emergency calls in one day for heroin overdoses — one involving the death of 39-year-old Adrian R. Dunn of Bemidji. He overdosed on Feb. 27 at a Bemidji apartment.

Three other people were hospitalized, two on calls in and around Bemidji and the last on the Leech Lake Indian Reservation, the Sheriff's Office said.

Late last spring, a federal grand jury indicted 41 people in a conspiracy that distributed heroin, methamphetamine and other drugs across the Upper Midwest and on two large Minnesota Indian reservations. At least 10 people were booked into the Beltrami County jail. U.S. Attorney Andrew Luger said then that the illicit drugs from Detroit and Chicago were being sold to Indian communities in Minnesota and elsewhere.

In the Twin Cities in 2014, a record-high 14.6 percent of admissions to addiction treatment programs were for heroin, according to Carol Falkowski, former director of the alcohol and drug abuse division at the state Department of Human Services and now with Drug Abuse Dialogues, a private provider of educational workshops.