He taught cops how to fight crypto crime. Now he's accused of running a $100 million dark web drug market.

• A Taiwanese crypto expert is accused of running a $100 million dark web drug market.
• Feds say he operated the drug marketplace and blackmailed its users in its final days.
• Just two months ago, he lectured police on tracing cryptocurrency and fighting cybercrime.

A 23-year-old Taiwanese crypto expert known for posting his qualifications on LinkedIn, working at an embassy, and lecturing police officers on cybercrime, may have been leading a questionable double life.

Lin Rui-siang stands accused of running a $100 million dark web drug market, attempting to blackmail its users, and instructing others on how to evade anti-money-laundering investigators.

According to the Department of Justice, Lin was arrested at John F. Kennedy Airport on Monday, and was charged with engaging in a continuing criminal conspiracy, narcotics conspiracy, conspiracy to sell adulterated and misbranded medication, and money laundering.

Federal prosecutors say that he owned and operated Incognito Market, a dark web drug market selling heroin, cocaine, oxycodone, and other illicit substances.

According to WIRED, which was the first to report on this, two months ago Lin led a course for St. Lucia Police titled "Cyber Crime and Cryptocurrency" about how to trace cryptocurrency.

In April, the Government of St. Lucia published a press release praising the four-day course, sponsored by the Taiwanese government, which it said 30 members of the police force had completed.

The press release said Lin had "used his professional background and qualifications in the field" to help the Royal St. Lucia Police Force enhance its cybercrime-fighting abilities.

While this likely referred to Lin's role as a diplomatic IT specialist at the Taiwanese embassy, the DoJ alleges that his cybercrime expertise had more nefarious origins.

Since Incognito Market was launched in October 2020 and closed in March of this year, the marketplace sold more than $100 million worth of narcotics, the DoJ said. The DoJ said Lin used the pseudonyms "Pharoah" and "faro."

According to the Justice Department, the website had its own "bank" to facilitate transactions, which allowed users to deposit cryptocurrency.

In a criminal complaint against Lin, an FBI investigator said customers and vendors used Monero, which uses privacy-enhancing technologies, and bitcoin.

The indictment claims that Lin closed the drug marketplace in or around March, and that he refused to return money stored in the "bank" to vendors and customers.

It also said that he threatened to leak users' transaction history unless they paid a fee.

According to the indictment, a message on the website landing page read: "YES, THIS IS AN EXTORTION!!!"

WIRED reported that Lin also operated a web service called Antinalysis, which charged users a fee to check whether their crypto could be linked to criminal transactions.

The outlet said that "Pharoah" posted on a dark web market forum that its aim was to help users evade anti-money-laundering investigators.

If convicted, Lin faces life in prison.

The investigation was led by the FBI, Homeland Security Investigations, the Drug Enforcement Administration, the Food and Drug Administration's Office of Criminal Investigations, and the New York Police Department.

"This arrest underscores the dedicated, ongoing efforts of law enforcement to identify and dismantle illicit drug networks operating from every shadowy recess of the marketplace," NYPD Commissioner Edward A. Caban said in a statement.