President Trump tweeted about a "Spy in the Trump Campaign" early Friday morning, citing a claim made by a Fox Business Network host. It marks the second time in two days that Mr. Trump has suggested federal law enforcement might have placed a spy on his presidential campaign.

"'Apparently the DOJ put a Spy in the Trump Campaign,'" the president tweeted, citing Fox Business host David Asman. "'This has never been done before and by any means necessary, they are out to frame Donald Trump for crimes he didn't commit.' David Asman @Lou Dobss @GreggJarrett Really bad stuff!"

“Apparently the DOJ put a Spy in the Trump Campaign. This has never been done before and by any means necessary, they are out to frame Donald Trump for crimes he didn’t commit.” David Asman @LouDobbs @GreggJarrett Really bad stuff! — Donald J. Trump (@realDonaldTrump) May 18, 2018

The president continued with that sentiment in a tweet later Friday morning, saying "reports" indicate "there was indeed at least one FBI representative implanted, for political purposes, into my campaign for president."

Reports are there was indeed at least one FBI representative implanted, for political purposes, into my campaign for president. It took place very early on, and long before the phony Russia Hoax became a “hot” Fake News story. If true - all time biggest political scandal! — Donald J. Trump (@realDonaldTrump) May 18, 2018

Mr. Trump tweeted Thursday that "word seems to be coming out that the Obama FBI" spied on the campaign with an informant, citing a National Review article raising the possibility of an FBI spy on Mr. Trump's campaign.

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"If so, this is bigger than Watergate!" he tweeted.

Wow, word seems to be coming out that the Obama FBI “SPIED ON THE TRUMP CAMPAIGN WITH AN EMBEDDED INFORMANT.” Andrew McCarthy says, “There’s probably no doubt that they had at least one confidential informant in the campaign.” If so, this is bigger than Watergate! — Donald J. Trump (@realDonaldTrump) May 17, 2018

The National Review article cites work by Rep. Devin Nunes, an ardent Trump supporter and head of the House intelligence committee, who has demanded information on an FBI source in the Russia investigation. The New York Times reported separately this week that at least one government informant met several times with Carter Page and George Papadopoulos, both former foreign policy advisers on Trump's Republican campaign. The newspaper attributed the information to current and former FBI officials.

The Washington Post reported Thursday that Mr. Trump's circles are ramping up a campaign to undermine the special counsel's Russia investigation by exposing the role of a top-secret FBI source. According to the Post, DOJ and intelligence agency leaders warn that publicly identifying the confidential source would imperil operations and endanger lives.

But the president's newest personal lawyer has said publicly that it's unclear if there was a spy on the Trump campaign.

Rudy Giuliani told CNN's Christopher Cuomo Friday morning that, "We don't know for sure — nor does the president — that there really was" an informant. Giuliani said they have simply been "told that" but "don't know" for sure if that's the case.

The president's tweets are just the latest instance of what seems to be a growing rift between the president, the DOJ and intelligence agencies. Mr. Trump has often criticized his own administration's leadership there.