Referenews

Twitter also suspended the official account of Mastodon, a social-media platform that has gained prominence in recent months, also without explanation. A representative for Mastodon didn’t immediately respond to a request for comment.

Ella Irwin, Twitter’s head of trust and safety, declined in an email to comment on specific user accounts. Mr. Musk indicated that the suspensions were linked to an episode on Wednesday in which the platform suspended an account that tracked and tweeted the movements of Mr. Musk’s private jet using public information. The account, called @ElonJet, was run by a student at the University of Central Florida named Jack Sweeney and had about 500,000 followers.

Twitter also suspended Wednesday several other accounts Mr. Sweeney ran that tracked the flights of public figures.

The same day, Twitter changed its private information policy to prohibit sharing other people’s live locations in most instances.

Mr. Musk tweeted last month: “My commitment to free speech extends even to not banning the account following my plane, even though that is a direct personal safety risk.” On Wednesday, though, he equated the practice to doxxing, or the publishing of private information online with malicious intent, tweeting: “Real-time posting of someone else’s location violates doxxing policy, but delayed posting of locations are ok.”

Mr. Musk also said Twitter would block accounts that post links to sites with real-time location information.

The move to suspend journalists’ accounts is the latest extraordinary twist in Mr. Musk’s stewardship of Twitter. He has said that he intends to make the platform a bastion of free speech, with transparent rules governing any content decisions.

But he also has taken several steps that have added confusion regarding Twitter’s content policies, including a decision to suspend the account of Kanye West after the rapper posted a swastika image in a tweet, and the sudden dissolution of Twitter’s Trust and Safety Council, a six-year-old collection of outside groups that advised the platform on enforcing its content policies.

At least some of the journalists whose accounts were suspended had tweeted earlier Thursday referencing the @ElonJet account, versions of which remain active on other platforms.

The Mashable journalist who was suspended said he didn’t share any location data, in concurrence with Twitter’s new terms, nor did he share any links to @ElonJet or other location tracking accounts.

Ms. Irwin said in her email: “Without commenting on any specific user accounts, I can confirm that we will suspend any accounts that violate our privacy policies and put other users at risk.”

Ms. Irwin cited Twitter’s policy update Wednesday barring the posting of “live location information,” including travel routes or other information. “We don’t make exceptions to this policy for journalists or any other accounts,” Ms. Irwin added.

Mr. Musk tweeted Thursday evening: “Same doxxing rules apply to ‘journalists’ as to everyone else.”

The official Twitter account of Mastodon, before it was suspended, tweeted: “Did you know? You can follow @ElonJet on Mastodon over at mastodon.social/@elonjet.”

Some users said late Thursday that Twitter was blocking them from posting other links to Mastodon, including links to their own Mastodon profiles.

Ms. Irwin didn’t immediately respond to a request for comment about the blocking of posts linking to Mastodon.

It couldn’t be determined how long the suspensions would last. One journalist said on Mastodon that he received a notice from Twitter that his account had been permanently suspended.

Mr. Musk said Thursday night accounts engaged in doxxing would be suspended for seven days. He later tweeted a poll asking whether Twitter should reinstate the suspended accounts now or in seven days.

The move to suspend the journalists’ accounts could attract scrutiny from regulators, especially in the European Union, where a new law governing online content will start applying to large social-media platforms such as Twitter around the middle of next year.

Věra Jourová, the EU’s vice president for values and transparency, called the suspensions worrying. The new law, called the Digital Services Act, “requires respect of media freedom and fundamental rights,” she wrote on Twitter. She said Mr. Musk “should be aware of that. There are red lines. And sanctions, soon.”

Lori Trahan, a Democratic congresswoman from Massachusetts, tweeted Thursday night that her team had met with Twitter staff and were told “that they’re not going to retaliate against independent journalists or researchers who publish criticisms of the platform.” She added: “Less than 12 hours later, multiple technology reporters have been suspended. What’s the deal, @elonmusk?”

—Kim Mackrael and Alexa Corse contributed to this article.

Write to Meghan Bobrowsky at meghan.bobrowsky@wsj.com