A red notice has been issued by Interpol for an alleged Canadian mobster and fentanyl dealer who has evaded police since November.

Wojciech Grzesiowski, of Innisfil, Ont., was one of more than a dozen people named as charged or wanted by the RCMP last fall in a four-year cross-border investigation into fentanyl and organized crime, and is the only one who has yet to be arrested.

At the November news conference for the RCMP-led Project OTremens, police described Mr. Grzesiowski and his co-accused – including brothers Domenic and Giuseppe Violi, sons of slain Montreal mob boss Paolo Violi – as "well-known" members of organized crime.

Story continues below advertisement

Charges were laid at that time against nine men, and Canada-wide warrants were issued for five outstanding suspects, including Mr. Grzesiowski.

At that time, Toronto-based management and technology firm Peritus Business Consulting listed him as managing partner of business operations on its website, although his name has since been removed. The company did not respond to calls and e-mails from The Globe and Mail.

Mr. Greziowski, 40, holds citizenship in both Canada and Poland, where he was born. He has also done business in Vietnam.

A red notice is issued by Interpol and used "to seek the location and arrest of wanted persons with a view to extradition or similar lawful action."

It is a rare move, but one police feel is warranted given the charges Mr. Grzesiowski is facing, including instructing the commission of an offence for a criminal organization, commission of an offence for a criminal organization, possession of property obtained by crime, possession for the purpose of trafficking, and trafficking drugs, including fentanyl.

In a 2012 interview with the Financial Post, Mr. Greziowski (spelling his first name as "Wojtek") spoke about his fight with testicular cancer two years earlier and the care he received at Princess Margaret Hospital. Mr. Greziowski is described as a busy young professional "often jetting off to Asia and Europe for work."

He spoke of how the health scare affected him, and the lessons he took away from it: "Everyone has a path in life. But what I went through was a traumatic experience and it's impossible to go back to that original path. You have to start a new one," he said

Story continues below advertisement

Project OTremens began in 2013, when the RCMP encountered an opportunity to infiltrate the "higher echelons" of organized crime with the help of a well-connected police agent – a trusted associate and official "made," or full member, of the New York-based Bonanno crime family, according to court documents.

A parallel but separate investigation across the border by the Federal Bureau of Investigation into the Cosa Nostra in New York led to charges against alleged members and associates of the notorious Bonanno and Gambino crime families.

One of the most lauded seizures in Project OTremens was the undercover purchase of six kilograms of fentanyl and carfentanil. Mere grains of these potent opioids are enough to be lethal.

The investigation also highlighted organized crime's ability "to corrupt people in positions of public trust," police said in November.

During their investigation, police said, it came to light that a Toronto Police Service employee was allegedly making database queries on behalf of a criminal organization involving Mr. Grzesiowski. Erin Maranan has been charged with 20 counts of breach of trust.

The first resolution in the case came Monday, with a guilty plea from Vaughan, Ont., drug dealer Adriano Scolieri. The 31-year-old café owner was sentenced to 13 years and eight months in prison for drug trafficking, which included three kilograms of fentanyl that he sold to the police agent.

Story continues below advertisement

In return for Mr. Scolieri's plea Monday, charges against his friend and Project OTremens co-accused Nicholas Valentine were dropped. According to conversations recorded by police, Mr. Scolieri was well aware of the dangers of fentanyl.

"My buddy just OD'd off it," he told the police agent last October.

"A friend of yours?" the agent asked. "He died?"

"Yeah, I went to his viewing yesterday," Mr. Scolieri replied.

"Jesus Christ, how old was he?" the agent asked.

"Thirty-three. He thought he was doing coke," he said.

Story continues below advertisement

Mr. Scolieri was arrested a month later, while selling the agent two kilograms of the drug at an Oakville, Ont., motel.

After his guilty plea, Mr. Scolieri's lawyer, Gregory Lafontaine, described his client as a "stand-up guy" for asking that Mr. Valentine's charges be dropped, and accepting his responsibility so early on.

"This is a fitting sentence, which has been significantly discounted to reflect a very early plea," Tom Andreopoulos, deputy chief federal prosecutor for the Public Prosecution Service of Canada, said.

Over the span of Project OTremens, Mr. Andreopolous said Mr. Scolieri "revealed himself as an active, high-level criminal operative who had the ability to obtain and traffic a variety of criminal commodities."

He noted that the three kilograms of fentanyl that Mr. Scolieri is convicted of trafficking represents thousands of dosages of the drug.