A massive bug in Facebook has removed several legitimate posts, news and comments about new coronavirus from some leading media outlets like USA Today, Buzzfeed and Medium.

Aimed at curtailing the spread of fake and mischievous health information around COVID-19, Facebook’s News Feed spam filter blocked URLs of legitimate websites.

“It looks like an anti-spam rule at FB is going haywire. Facebook sent home content moderators yesterday, who generally can’t WFH (work from home) due to privacy commitments the company has made. We might be seeing the start of the ML going nuts with less human oversight,” tweeted former chief security officer at Facebook.

Guy Rosen, Vice President, Product Management at Facebook replied: “We’re on this – this is a bug in an anti-spam system, unrelated to any changes in our content moderator workforce. We’re in the process of fixing and bringing all these posts back”.

Later, he said Facebook has “restored all the posts that were incorrectly removed, which included posts on all topics – not just those related to COVID-19”.

According to the company, this was an issue with an automated system that removes links to abusive websites, “but incorrectly removed a lot of other posts too”.

A Twitter user posted: “It’s not just news articles. A community flier asking for emergency donations of food to the needy in our community was blocked. A friend in Canada had posts from Royal Canadian Mounted Police blocked. It’s very widespread”.

Top tech giants Facebook, Google, LinkedIn, Microsoft, Reddit, Twitter and YouTube have come together to help fight the fake news and misinformation related to COVID-19 on their platforms.

Facebook and Instagram have already announced to ban ads and commerce listings selling medical face masks on their platforms to stop people from exploiting the coronavirus emergency.

Facebook said that coronavirus-related searches on its platform would be greeted with an automatic pop-up featuring information from the WHO.