The US president has claimed that those investigating the case have allegedly violated procedure.
"Congratulations to @JudicialWatch and @TomFitton on being successful in getting the Carter Page FISA documents. 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.
READ MORE: Trump Tweets Hillary Clinton Interview Talking About ‘Strong Russia'
Trump added that his 2016 campaign was "spied upon" for the benefit of his opponents.
Looking more & more like the Trump Campaign for President was illegally being spied upon (surveillance) for the political gain of Crooked Hillary Clinton and the DNC. Ask her how that worked out — she did better with Crazy Bernie. Republicans must get tough now. An illegal Scam!
— Donald J. Trump (@realDonaldTrump) July 22, 2018
Last May, Donald Trump addressed media reports that the FBI had planted a mole in his entourage amid the campaign's alleged ties to Russia, stating, however, that the operation was politically-motivated and began long before the probe into the issue started.
Russian officials have repeatedly stressed that Moscow has never tampered with the US elections, noting that no accusations against Russia have been substantiated.