WASHINGTON (AP) — President Donald Trump tried to cast fresh doubt Monday on the federal investigation into Russian election interference in the 2016 presidential election, calling it a "fraud and a hoax designed to target Trump" and demanding an immediate end to the "Witch Hunt."

Trump also said former campaign adviser Carter Page, the subject of government documents released over the weekend, wasn't a spy or an agent of Russia.

Lawmakers from both political parties said that the documents don't show wrongdoing and that they even appear to undermine some previous claims by top Republicans.

"Carter Page wasn't a spy, wasn't an agent of the Russians – he would have cooperated with the FBI. It was a fraud and a hoax designed to target Trump," the president said in a series of tweets quoting Tom Fitton, president of the conservative watchdog group Judicial Watch.

Fitton was interviewed Monday on "Fox and Friends," an appearance Trump tweeted about.

"A disgrace to America," Trump's tweet continued. "They should drop the discredited Mueller Witch Hunt now!"

The president was responding to the Justice Department's Saturday release of documents related to the wiretapping of Page. Trump has asserted without evidence that the documents, heavily redacted and released Saturday under the Freedom of Information Act, "confirm with little doubt" that intelligence agencies misled a special court that approved the wiretap warrant.

But lawmakers from both political parties said that the documents don't show wrongdoing and that they even appear to undermine some previous claims by top Republicans on the basis for obtaining a warrant against Page.

Visible portions of the documents show the FBI telling the court that Page "has been collaborating and conspiring with the Russian government." The agency also told the court that "the FBI believes Page has been the subject of targeted recruitment by the Russian government."

Trump's tweets landed as he continues to try to reassure the country that he accepts that longtime foe Russia interfered in the 2016 election, despite his public undermining of U.S. intelligence agencies in Helsinki while standing alongside Russian President Vladimir Putin.

"So President Obama knew about Russia before the Election," Trump tweeted late Sunday. "Why didn't he do something about it? Why didn't he tell our campaign? Because it is all a big hoax, that's why, and he thought Crooked Hillary was going to win!!!"

READ MORE: The many different ways Trump has described Putin and Russian election interference

White House press secretary Sarah Huckabee Sanders said Monday that Trump was "obviously" referring to allegations of collusion between his presidential campaign and Russian agents.

U.S. intelligence agencies unanimously concurred that Russia interfered in the 2016 campaign. Trump only reluctantly accepted their assessment amid the firestorm of last week's reaction to his comments at a summit news conference with Putin.

"Obviously the president is talking about the collusion with his campaign," Sanders said. "He's been very clear that there wasn't any. I think he's said it about 1,000 times."

In Monday's tweets, Trump again mischaracterized the documents released by the FBI this weekend that provided grounds for its surveillance of Page. Trump claimed without evidence that the FBI inappropriately used political research by British spy Christopher Steele to mislead the court into granting a wiretap order, then classified the documents to "cover up misconduct."

That's not what the documents show, though. Released online under the Freedom of Information Act, the documents note the political ties to Steele's work but said it still believed some of his report to be "credible."

The FBI said it suspected Page had been "collaborating and conspiring with the Russian government." It told the court that "the FBI believes Page has been the subject of targeted recruitment by the Russian government."

Page denies being a foreign agent.

Special Counsel Robert Mueller is investigating potential collusion between Russia and Trump's campaign. Two Trump associates, former national security adviser Mike Flynn and campaign foreign policy aide George Papadopoulos, pleaded guilty last year to charges brought by Mueller alleging they had lied to the FBI about their Russia contacts.

The documents released over the weekend were part of officials' application for a warrant to the secretive foreign intelligence surveillance court.

"As usual they are ridiculously heavily redacted but confirm with little doubt that the Department of 'Justice' and FBI misled the courts. Witch Hunt Rigged, a Scam!" Trump tweeted over the weekend.

While the documents confirm that the FBI relied, in part, on information from Steele to obtain the initial warrant, they also show how the FBI informed the court of his likely motivation.

A page-long footnote in the warrant application lays out the FBI's assessment of Steele's history and the likely interest of his backer, adding that despite the political concern, the bureau believed at least some of his report to be "credible."

Democratic Rep. Adam Schiff of California, a ranking member on the House Intelligence Committee, said the documents detail "just why the FBI was so concerned that Carter Page might be acting as an agent of a foreign power."

READ MORE: The giant timeline of everything Russia, Trump and the investigations

"It was a solid application and renewals signed by four different judges appointed by three different Republican presidents," Schiff said on ABC's "This Week."

Republican Sen. Marco Rubio of Florida said he didn't think the FBI did anything wrong in obtaining warrants against Page.

"I have a different view on this issue than the president and the White House," Rubio said Sunday on CBS' "Face the Nation." "They did not spy on the campaign from anything and everything that I have seen. You have an individual here who has openly bragged about his ties to Russia and Russians."

In a 2013 letter, Page had described himself as an "informal adviser' to the Kremlin but now said "it's really spin" to call him an adviser.

Page has not been charged with a crime, but he has been interviewed by the FBI and congressional investigators about his ties to Russia. White House officials have argued that Page, announced by the president in early 2016 as a foreign policy adviser, played only a minor role in the Trump campaign.

The documents released Saturday include the FBI's October 2016 request to surveil Page and several renewal applications. It marks the first time in the more than 40-year history of the highly secretive court that underlying documents for a warrant have been released.