Police in Halifax have seized a large amount of an opioid even stronger than fentanyl, which they say has a "great potential to be fatal."

Over two weeks in February, Halifax Regional Police say investigators in the Guns and Gangs Unit of the Integrated Criminal Investigation Division made a number of searches in relation to a drug trafficking case.

Through the investigation, police searched a residence on Dentith Road in Spryfield on Feb. 12 and seized multiple items, including about 1,900 unknown pills.

Five people were charged soon after with various drug trafficking and possession charges.

The drugs were sent to Health Canada for analysis. They confirmed the tablets are isotonitazene, a synthetic opioid they told police was "similar to but stronger than fentanyl," according to a news release.

'Great potential to be fatal'

"Our primary concern was to let people know that it was out there, that it's extremely dangerous, and if they've come across it they should make sure they get medical attention," police spokesperson Const. John MacLeod said Thursday.

"It definitely has a great potential to be fatal."

The pills are a white triangle shape with "M" carved on one side and "8" on the other.

MacLeod said people should always keep in mind the opioid might be misrepresented as another drug. While he couldn't speculate on how it would be sold, MacLeod said the pills they seized resemble one form of hydomorphone.

Given its potency, MacLeod said people may need several shots of naloxone to counter an overdose.

Halifax police are still investigating the origin of the drugs.

MacLeod said this is the first time the opioid has been seized in Halifax, although it has also appeared in Saint John and Calgary.

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