Twitter's push to stop internet trolls has reportedly resulted in the accounts of some top Republicans being hidden from search results.

On Thursday, President Trump slammed the social media company over this so-called "shadow banning" of prominent Republicans. "We will look into this discriminatory and illegal practice at once! Many complaints," he said in a tweet, without elaborating.

The shadow banning was first noticed by Vice News. Among those ensnared were GOP chairwoman Ronna McDaniel, Donald Trump Jr's spokesman Andrew Surabian, and Republican lawmakers Jim Jordan and Matt Gaetz.

The shadow banning occurred through Twitter's search bar. Normally, it will auto-populate a drop-down menu with the relevant results as you begin typing the account holder's name.

However, the search bar was refusing to show the Twitter accounts for the affected Republicans, even after you entered their full name. To find them, you'd have to type the name, click enter, and hope it'd return with the correct result.

The shadow banning didn't affect all prominent Republicans. Conservative pundits, such as Ann Coulter, Sean Hannity, and Mike Cernovich, were still auto-populating in the search bar. So was President Trump. Nevertheless, Republicans are slamming Twitter, claiming the whole incident adds more evidence that the company discriminates against conservative viewpoints.

"Silicon Valley's bias against conservatives is apparent. It's time they acknowledge it and tell us what they are going to do to fix it," tweeted Republican lawmaker Steve Scalise.

In response to the complaints, Twitter said the shadow banning wasn't politically driven. In May, the company announced a new policy to stop internet trolls over the platform by preventing their tweets from appearing at the top of searches. To find the offending tweets, the company relies on computer algorithms and what it calls "behavioral signals." This includes how a Twitter account interacts with other accounts that have violated the platform's rules.

"To be clear, our behavioral ranking doesn't make judgments based on political views or the substance of tweets," Twitter product head Kayvon Beykpour said in a series of tweets. "Our usage of the behavior signals within search was causing this to happen and making search results seem inaccurate. We're making a change today that will improve this."

The affected Republicans are no longer shadow banned. But the whole incident underscores the challenges Twitter is facing to both support free speech and fight abuse over the platform. To address the criticism, the company is considering making its algorithms on ranking tweets transparent to the public.

"It suffices to say we have a lot more work to do to earn people's trust on how we work," Twitter CEO Jack Dorsey tweeted on Wednesday.