Two men were charged with helping a U.S. cryptocurrency expert evade U.S. sanctions on North Korea by discussing blockchain technology at a conference held in the isolated East Asian country.

Alejandro Cao de Benos of Spain and Christopher Emms, a U.K. citizen, were charged in a superseding indictment with conspiracy to violate U.S. sanctions, the Department of Justice said Monday. Cao de Benos and Emms allegedly worked with Virgil Griffith, a former Ethereum Foundation cryptocurrency scientist, who participated in a 2019 blockchain and cryptocurrency conference in the North Korean capital, Pyongyang, the department said.

Griffith was sentenced to more than five years in prison this month after pleading guilty to violating sanctions. Cao de Benos, 47, and Emms, 30, face as many as 20 years in prison if convicted. They are not in U.S. custody.

Alejandro Cao de Benos in 2016 | AFP / Getty Images via Bloomberg
Alejandro Cao de Benos in 2016 | AFP / Getty Images via Bloomberg

Prosecutors claim Emms, a cryptocurrency businessman, told North Korean officials that blockchain technology makes it possible to "transfer money across any country in the world regardless of what sanctions or any penalties that are put on any country.”

Cao de Benos, founder of the Korean Friendship Association — a group friendly to the regime of North Korean dictator Kim Jong Un — allegedly helped coordinate official approval for Griffith’s participation in the conference.

Griffith, 39, admitted he ignored specific State Department warnings against attending the conference. He was arrested in November 2019 in Los Angeles on charges of providing technical blockchain information to the regime. Prosecutors said the information could be used to help the country launder money and evade sanctions.

Griffith was the subject of a 2008 New York Times Magazine profile that described him as a "cult hacker” and dubbed him the "Internet Man of Mystery."