Donald Trump took his attacks on Hillary Clinton to a new level Wednesday when the Republican presidential candidate essentially called on Russia to hack his rival’s email.

“Russia if you’re listening, I hope you’re able to find the 30,000 emails that are missing,” Trump said. “I think you will probably be rewarded mightily by our press.”

Trump made the comment during a news conference in Florida while discussing the United States’ relationship with Russia, expressing his belief that Russian President Vladimir Putin doesn’t respect Clinton.

He then doubled down on the hacking suggestion by tweeting something similar.

“If Russia or any other country or person has Hillary Clinton’s 33,000 illegally deleted emails, perhaps they should share them with the FBI!” he tweeted.

The Clinton campaign’s senior policy adviser, Jake Sullivan, released a statement calling Trump’s comments a “national security issue.”

“This has to be the first time that a major presidential candidate has actively encouraged a foreign power to conduct espionage against his political opponent,” Sullivan said in the statement. “That’s not hyperbole, those are just the facts. This has gone from being a matter of curiosity, and a matter of politics, to being a national security issue.”

Trump has now blended together two hot button issues surrounding the 2016 presidential race: The recent release of sensitive emails and documents from the Democratic National Committee by WikiLeaks, which intelligence experts have suggested could have been the work of the Russian government, and the recent decision from the U.S. attorney general not to pursue criminal charges against Clinton in connection with her email scandal.