Inside a Wild Bitcoin Heist: Five-Star Hotels, Cash-Stuffed Envelopes, and Vanishing Funds

As Kent Halliburton stood in a bathroom at the Rosewood Hotel in central Amsterdam, thousands of miles from home, running his fingers through an envelope filled with €10,000 in crisp banknotes, he started to wonder what he had gotten himself into.

Halliburton is the cofounder and CEO of Sazmining, a company that operates bitcoin mining hardware on behalf of clients—a model known as “mining-as-a-service.” Halliburton is based in Peru, but Sazmining runs mining hardware out of third-party data…