Three North Koreans have been indicted in the crippling 2014 Sony Pictures Entertainment hack and a wide-ranging scheme to steal and extort more than $1 billion in cash and cryptocurrency from banks and companies based across the globe, federal prosecutors said Wednesday.

The indictment describes a vast and multilayered scheme that went well beyond the Sony attack, targeting international banks and cryptocurrency companies. The defendants deployed malicious cryptocurrency applications and developed and fraudulently marketed a Blockchain platform, striking financial institutions and companies in multiple continents, prosecutors said.