It only took one man to shut down North Korea’s internet in one fell swoop and expose the country’s frail digital infrastructure in early 2022, but the mysterious figure behind the attacks now says the hard part came later — when he tried to convince the U.S. government that what he was doing was right.

Using the pseudonym P4x, the cybersecurity researcher took the servers hosting North Korea’s websites and email services offline with distributed denial-of-service (DDoS) attacks.