Updated

The reporter who helped break the story over the U.S. government's broad surveillance programs lit into NBC News host David Gregory on Sunday for asking why the reporter shouldn't be charged with a crime.

"I think it's pretty extraordinary that anybody who would call themselves a journalist would publicly muse about whether or not other journalists should be charged with felonies," Glenn Greenwald shot back on NBC's "Meet the Press."

Greenwald was the first to report, in The Guardian, about the government's widespread collection of U.S. phone data. Both The Guardian and The Washington Post have used leaked materials from former National Security Agency contractor and now-fugitive Edward Snowden for their reports.

Gregory, in a provocative question at the end of his interview Sunday with Greenwald, asked the following:

"To the extent that you have aided and abetted Snowden, even in his current movements, why shouldn't you, Mr. Greenwald, be charged with a crime?"

Greenwald said the "assumption" in the question was "without evidence."

He cited the very-recent controversy over the Justice Department's decision to seize the email records of Fox News correspondent James Rosen. In doing so, the government submitted an affidavit that called Rosen a likely criminal "co-conspirator" as part of an unauthorized leak. Rosen was never charged, though the alleged source of the leak was.

Amid widespread outcry and under President Obama's direction, the Justice Department is now taking a second look at its policies for cases that involve journalists.

Greenwald said the administration was effectively trying to "criminalize investigative journalism" and told Gregory: "If you want to embrace that theory, it means that every investigative journalist in the United States who works with their sources, who receives classified information is a criminal, and it's precisely those theories and precisely that climate that has become so menacing in the United States."

Gregory said he wasn't "embracing anything," just posing a question that was "raised by lawmakers."

Greenwald did not appear to accept the explanation. He later took to Twitter to further criticize Gregory.

"Who needs the government to try to criminalize journalism when you have David Gregory to do it?" he tweeted.