Twitter is now blocking tweets that include links to Mastodon, its competitor

• Twitter appears to be banning the posting of links to its competitor, Mastodon.
• Insider's attempt to publish tweets containing Mastodon links were met with an error message.

Twitter appears to be blocking tweets that contain links to Mastodon, a competing social-media platform.

On Thursday evening, Insider attempted to publish ten tweets from three separate Twitter accounts, all containing links to various Mastodon user profiles. Each attempt was met with an error message that read: "Your Tweet couldn't be sent because this link has been identified by Twitter or our partners as being potentially harmful. Visit our Help Center to learn more."

Other Twitter users also noticed on Thursday evening that they were unable to post links to Mastodon, a platform often touted as an alternative to Twitter.

Among them was NBC journalist Ben Collins, who found a workaround to post his Mastodon link by breaking up the URL with a set of brackets.

Also on Thursday, Twitter suspended the official Mastodon Twitter account. The move appeared to be a part of a raft of account suspensions that included the accounts of CNN journalist Donie O'Sullivan, The Washington Post's Drew Harwell, The New York Times' Ryan Mac, as well as independent journalists Aaron Rupar, Keith Olbermann, and Tony Webster.

Musk and representatives for Mastodon did not immediately respond to Insider's request for comment.

This is a developing story. Please check back for updates.