Facebook CEO Mark Zuckerberg reacted to accusations its firm’s “trending” issues list was suppressing conservative media, saying on Thursday the company was running an investigation.

No signs of alleged exploitation was discovered, but “if we locate anything against our principles, you have my commitment that we’ll take added measures to address it,” Zuckerberg wrote in a Facebook post.

Technology news outlet Gizmodo reported on Monday that a former Facebook worker alleged that posts from conservative outlets — especially when written about issues that were conservative — were intentionally omitted from the sidebar of popular reports of Facebook.

The allegations have been denied by the social media giant amid outrage over the claims.

Facebook said an algorithm, subsequently audited — never controlled — by review team members established the popularity of news stories to verify the issues were in fact.

There was no evidence that direction mandated or was conscious of any political prejudice on the job, Gizmodo reported, noting that one former worker “described the omissions as a function of his co-workers’ judgements.”

Gizmodo reported that workers were told to place reports deemed as significant by direction in the news feed that was trending if they were not creating much buzz.