President Donald Trump on Thursday ripped his favorite social media platform, criticizing Twitter for “shadow banning” Republicans, a vague accusation the commander-in-chief said was "discriminatory" and "illegal.”

“Twitter 'SHADOW BANNING' prominent Republicans. Not good,” Trump wrote on Twitter. “We will look into this discriminatory and illegal practice at once! Many complaints.”

Twitter “SHADOW BANNING” prominent Republicans. Not good. We will look into this discriminatory and illegal practice at once! Many complaints. — Donald J. Trump (@realDonaldTrump) July 26, 2018

“Shadow banning” is a term popular in conservative circles that refers to the idea that Twitter has quietly made the profiles and tweets of prominent conservative figures more difficult for users to see.

The latest batch of accusations of “shadow banning” centers around Twitter's search function. The profiles of prominent conservatives were not appearing in the autofill drop-down search function on the platform when users attempted to search for their profiles.

VICE News reported earlier this week that affected Republican profiles included Ronna Romney McDaniel, the chairwoman of the Republican National Committee, multiple conservative Republicans in Congress (including House Freedom Caucus Chairman Mark Meadows, R-N.C., and Rep. Jim Jordan, R-Ohio) and Donald Trump Jr.’s spokesman.

A spokesperson for Twitter said the company did not have anything to share about Trump’s tweet Thursday morning.

The spokesperson, however, denied outright that the company engages in shadow banning.

“As we have said before, we do not 'shadowban'. We are aware that some accounts are not automatically populating in our search box, and shipping a change to address this,” the spokesperson told NBC News in a statement. “The profiles, Tweets and discussions about these accounts do appear when you search for them. To be clear, our behavioral ranking doesn’t make judgments based on political views or the substance of Tweets.”

As of Thursday morning, the autofill problem appeared to have been fixed by Twitter.

The allegations come as Twitter is in the middle of a months-long campaign to police its platform for abuse, trolls, harassment and misinformation, after it became clear that Russia-linked accounts and bots were tied to “malicious activity” during the 2016 presidential election.

In March, Jack Dorsey, the company’s CEO, posted that he wanted to “increase the collective health, openness, and civility of public conversation, and to hold ourselves publicly accountable towards progress” and in May, the company announced it would be “integrating new behavioral signals into how Tweets are presented.”

Republicans, however, have accused the company of having taken actions that affect how easily their profiles can be found and seen on Twitter.