Trump's comment comes a day after Vice News reported that Republican Party chair Ronna McDaniel, a number of conservative Republican congressmen and Donald Trump Jr.'s spokesman stopped showing up in Twitter's auto-populated drop-down search box.
"Twitter 'SHADOW BANNING' prominent Republicans. Not good," the president tweeted. "We will look into this discriminatory and illegal practice at once! Many complaints."
Vice on Wednesday noted that Democrats' Twitter accounts aren't being impacted in the same way. Aside from McDaniel, the site mentioned Republican Reps. Mark Meadows of North Carolina, Jim Jordan of Ohio and Matt Gaetz of Florida, as well as Trump Jr. spokesman Andrew Surabian. It also said the verified account of Rep. Devin Nunes of California didn't show up in the search box, only his unverified one.
The report noted that the profiles appeared when conducting a full search, and would show up in the auto-populated search box if you already followed the account.
"We are aware that some accounts are not automatically populating in our search box and shipping a change to address this," a Twitter spokesperson told Vice after being presented with screenshots of the searches.
All of the accounts showed up in searches by CNET on Thursday morning.
"To be clear, our behavioral ranking doesn't make judgments based on political views or the substance of tweets," a Twitter spokesperson said, before pointing to a May blog post on how it presents content and to product lead Kayvon Beykpour's tweets about the changes it made on Wednesday.
Twitter CEO Jack Dorsey said in a tweet Wednesday, "It suffices to say we have a lot more work to do to earn people's trust on how we work."
The White House didn't immediately respond to a request for comment.
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