After months of undercover work, a group of Canadian and American police officers watched Robert Kiessling as he got in his car and pulled away from the home he shared with his partner and her two daughters in picturesque Kelowna, British Columbia.

They followed him that day this past January 9th, first as he dropped off his partner Katie about 20 minutes away, and then drove to the Canada Post office at a card shop downtown. He entered with a white envelope in hand, containing what they believed to be the deadly opioid fentanyl.

Kiessling likely didn’t realize Canadian and U.S. law enforcement had been watching his online activities since the previous September. That’s when the RCMP had first alerted their U.S. counterparts they had matched his identity to a fentanyl vendor on the dark web called DougFish44, also known as DF44, according to U.S. court documents obtained by VICE News.

Officers believed Kiessling was the mastermind behind DF44, a vendor who operated on dark web markets such as Dream, and the now shuttered AlphaBay, and listed hundreds of sales of fentanyl and Lean, a liquid containing codeine and other substances also known as “purple drank.”

A week after his arrest, Kiessling was found dead of an apparent suicide in Calgary, Alberta, where he grew up.

The 40-year-old was one of the targets of a large U.S. federal investigation dubbed “Operation Darkness Falls” that went after dark web drug dealers. In a press statement, the department described Kiessling as the third-largest fentanyl vendor in North America, and listed his arrest as one example of the operation’s accomplishments.

Operation Darkness Falls is part of the U.S. crackdown on the powerful synthetic opioids that have been linked to skyrocketing rates of overdoses and deaths. Last year saw record-breaking rates of opioid deaths: more than 30,000 in the U.S. and more than 4,000 in Canada, according to each government's statistics.

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The U.S. and Canada have been frequent collaborators in their efforts to stem the flow of powerful opioids that have ravaged both countries — and a number of cases so far have revealed a pattern of Canadian vendors allegedly coordinating or directly selling fentanyl and its analogues through the mail.

Operation Darkness Falls also netted Matthew and Holly Roberts, a San Antonio, Texas couple that police describe as the “most prolific” dark net fentanyl vendors in the world. Their charges are still pending.

“Today’s announcements are a warning to every trafficker, every crooked doctor or pharmacist, and every drug company, every chairman and foreign national and company that puts greed before the lives and health of the American people,” U.S. Attorney General Jeff Sessions states in the Operation Darkness Falls press release. “This Justice Department will use civil and criminal penalties alike and we will find you, put you in jail, or make you pay.”

This isn’t the first American opioid-related bust that has turned its attention north of the border — last year alone, U.S. officials indicted a Canadian man for allegedly running a fentanyl trafficking run from his prison cell in Quebec where he’s serving time for other drug-related convictions.

Details from Canadian authorities on that case have been virtually non-existent, and the same can be said of Operation Darkness Falls.

In that opaqueness, strange threads have emerged. Not much, for example, is publicly known about Kiessling, the only Canadian listed on the Operation Darkness Falls press release. And there appears to be confusion on the part of the police as to how he came to be released prior to his death.

He’s also not the only accused dealer linked to the operation to have wound up dead — Grace Bosworth, a 39-year-old Ohio woman who was arrested last year alongside her partner for dark web trafficking, killed herself amid ongoing criminal proceedings. Bosworth isn’t mentioned in the Operation Darkness Falls press release, but her partner, James Halpin, is.

Both were arrested last year and accused of accepting parcels by way of Canada, and mailing them out. Halpin, whom the U.S. Department of Justice said went by "MotleyFool" on the dark web, recently pleaded guilty "to his role as a national dark net fentanyl vendor."

**

Kiessling placed the envelope on the Kelowna post office counter to be mailed. Somewhere in his periphery, the RCMP was lying in wait on January 9, 2018 — a constable came forwarded placed him under arrest.

Upon inspection, officers found a white plastic baggie containing just over 10 grams of “a white powdery substance consistent with fentanyl or a fentanyl analogue” inside the envelope in question, according to an affidavit by U.S. postal inspector Michael Adams.

Kiessling was then escorted to the Kelowna detachment, where he remained in police custody for the next 24 hours, BC RCMP Spokesperson Annie Linteau told VICE News. That’s the maximum amount of time police can hold someone without charge in Canada. While Kiessling was being detained, the RCMP carried out two search warrants, which remain under seal in Canada, Linteau said.

The U.S. affidavit sheds some light on what unfolded.

It describes how the RCMP officers searched Kiessling's home and found a locked door to an office in the basement. Inside, they found a laptop displaying the Dream Market profile for DF44, shipping supplies, a safe, bulk currency, a scale, and “bags of white powder consistent with fentanyl.” They also found several red plastic cups that contained what the affidavit described as codeine syrup, also known as Lean.

The next day, on January 10th, an RCMP officer searched Kiessling’s car, a white 2015 Audi A5. Officers found an iPhone and receipts from a plastics company for 16-ounce bottles, the same type of bottles DF44 sold online containing the syrup.

Also on January 10th, according to Adams’ affidavit, two RCMP constables interviewed Katie Brown, who is described as Kiessling’s common-law partner.

“During the interview, Brown disavowed all knowledge of Kiessling’s activities and claimed she was not involved in the Darknet, or distribution of fentanyl,” Adams continued in the affidavit. “Brown further stated that Kiessling was the only person who had access to the room and computer utilized to access the dark web.”

Adams concluded there is probably cause to believe that Kiessling committed several federal crimes including manufacturing, distributing, and trafficking fentanyl and fentanyl analogues, importing illegal drugs, and smuggling goods into the U.S.

The U.S. affidavit and scraps of information from the RCMP are the only public accounts of what unfolded with Kiessling’s arrest. The details were kept secret by Canadian and U.S. officials until last week.

Kiessling was never charged in Canada in relation to this case, and the U.S. government was granted a sealing order shortly after his arrest to prevent him from finding out about the drug charges it was pursuing against him.

“Were he to become aware of these charges, he may flee, destroy evidence, and/or liquidate criminal proceeds,” the U.S. state attorney submitted in an Ohio on January 12, 2018.

It’s unclear whether Kiessling knew about these court proceedings.

That sealing order was lifted by the court just last week.

Kiessling’s case provides a glimpse into the inner workings of the RCMP’s involvement with international law enforcement partners as they grapple with dark web drug trafficking across borders amid a worsening opioid crisis.

When reached by phone, Kiessling’s father, Fritz Kiessling, declined to comment on his son’s death. Multiple attempts to reach Katie Brown and other relatives for comment were unsuccessful.

While the U.S. Department of Justice stated that Kiessling died by suicide, no Canadian law enforcement nor government department would confirm this citing privacy or ongoing investigations.

A Calgary Police spokesperson told VICE News over the phone that Kiessling was “located deceased on January 17th, and his death was ruled as non-criminal.”

RCMP spokesperson Annie Linteau told VICE News in an email that Kiessling was subject to an investigation by the RCMP for a “number of illegal activities centred around illicit drug production and distribution,” but wouldn’t say what type or drugs nor how long he was under investigation.

“It is our understanding that he has since died, and it would be inappropriate to comment further. As this remains part of an ongoing investigation we are unable to comment further at this time,” said Linteau.

While the U.S. Department of Justice stated in its press release that Kiessling had been released on a “bond” after his arrest, the RCMP confirmed to VICE News that was not the case.

“Mr. Kiessling was released 24 hours after his arrest as the RCMP continued their investigation,” an RCMP spokesperson said. When asked for the reason behind the discrepancy between the two statements from Canadian and American law enforcement regarding whether Kiessling was released on a bond, Linteau replied, “I do not know. I asked the investigator and he told me that the individual was released without any documents.”

**

In the course of just a few months, Ohio woman Grace Bosworth went from lauded local entrepreneur to an accused fentanyl smuggler living under house arrest, subjected to harsh messages on her public Facebook page regarding her alleged crimes.

In May of 2017, undercover U.S. law enforcement agents began purchasing fentanyl from a dark web vendor as part of their ongoing investigation. A Cincinnati postal inspector eventually linked a number of packages back to an address in the city where James Halpin, 30, and Grace Bosworth, 39, both lived, according to an affidavit filed in August 2017 by special agent of the U.S. Homeland Security Investigations in Ohio, Michael Grote, who also worked on the Kiessling matter.

“Bosworth’s leased Mercedes had been observed parked in front of that address,” Grote stated.

On the morning of June 7th, 2017, agents spotted cars belonging to Halpin and Bosworth parked outside a post office in Cincinnati. By the early afternoon, Halpern entered and picked up a Canadian Xpresspost parcel containing five grams of fentanyl, carfentanil, and other fentanyl analogues, according to Grote’s affidavit. He also mailed out three packages to various U.S. addresses, including one addressed to an undercover officer.

Halpin was promptly detained by law enforcement who also found “a small portion of untested fentanyl in a Camel snuff” after searching him.

In an interview, Halpin confessed that he had mailed as many as 35 packages containing between 50 to 100 mg each of fentanyl. Halpin told the officers that Bosworth had packaged the items, and he was tasked with mailing the drugs to the online customers. Further, according to the affidavit, Halpin claimed that Bosworth was the one who conducted the purchases and sales of the fentanyl online.

“Halpin said Bosworth would give him the parcels already packaged and ready to go,” the court document stated. “He admitted to receiving Canadian packages weekly since March of 2017, that contained 2 grams or more of fentanyl. He said he did not open the Canadian parcels, but rather gave them to Bosworth after he picked them up from the Post office.”

A search of Halpin and Bosworth’s home yielded a number of mailing receipts, seven orange baggies containing suspected fentanyl, and other drugs, were located in “a purse containing Bosworth’s belongings.”

In 2011, Bosworth was profiled by local media for founding Global 2 Local Language Solutions, a translation-services company.

Fluent in Spanish, she told FOX19 Now that she hoped to expand her business across the state. “You've got to get up every morning, and you've gotta push yourself and you've gotta make the sales calls and do the accounting and if you don't know how to do something, you've got to find the answer," Bosworth said at the time.

Before starting the company, she obtained a number of university degrees, according to her LinkedIn page, including an MBA in International Business and another Master’s in project management. She also had a criminal record dating back to 2010 for offences including theft and disorderly conduct.

Halpin’s LinkedIn states that he too worked at Global 2 Local as a chief operating officer from 2016 to July 2017, a month after he and Bosworth were first charged. While awaiting trial, Halpin and Bosworth were ordered to stay away from each other and complete substance abuse treatment and submit to mental health evaluations.

By October, according to court documents, Bosworth was living under house arrest and was proceeding with pre-indictment negotiations with the government.

Her Facebook profile had also been peppered with comments from people reacting to her criminal charges. “I lost a step daughter in January of a [fentanyl] od you piece of shit. I hope you rot in prison,” wrote one commenter about a year ago. “

“Manslaughter at least, My niece was just 20. I hope you burn,’ wrote another.

“What language do they speak in prison?” someone else commented.

On December 5th, Bosworth was found dead on the second floor of her home, after pre-trial services asked police to check on her because her GPS monitoring device indicated that she hadn’t left her house in three days. Her death was ruled a suicide by a prescription pill overdose, and a coroner’s report sent to VICE News noted that she had left a suicide note behind.

In a brief phone call this week, Bosworth’s former attorney, Louis Sirkin, said that Bosworth’s parents and sisters had mourned her death, and that the overall criminal process had taken its toll on her. Attempts to reach her relatives were unsuccessful.

It would be inappropriate to comment further, Sirkin said.