Greenwald replied Sunday that it was "pretty extraordinary" that someone who calls himself a journalist would ask whether other journalists should be charged with felonies.
Gregory said that the question of who is a journalist may be "up to a debate" with regard to Greenwald. The host added that he was asking a question, not taking a position.
Greenwald broke the story of Snowden's disclosure of U.S. government surveillance programs. Snowden was believed to have landed in Russia on Sunday -- possibly as a stopover before traveling to South America.
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