Former National Security Agency contractor Edward Snowden on Thursday lamented Julian Assange’s arrest by authorities outside the Ecuadorian embassy in London, calling the event “a dark moment” for freedom.

Snowden, 35, who lives in Moscow, Russia under political asylum after he leaked classified information to reporters, made a brief statement via Twitter about the Assange arrest. He linked to a video showing officials entering the embassy and removing a startled-looking Assange.