Blue checkmarks began to disappear from formerly verified Twitter accounts on Thursday, as policies implemented under new owner Elon Musk began to take hold.

Musk, who purchased the company for $44bn in 2022 and has thus far struggled to make it profitable, has been threatening to remove what he called “legacy blue checks” for months now. The checkmark previously denoted accounts that had been verified for authenticity and was given to accounts of celebrities, journalists and media outlets.

Now users seeking verification will have to pay for Twitter Blue, a controversial $8 a month subscription program under which any account can obtain a blue checkmark.

The rollout of the changes on Thursday was chaotic. Numerous high-profile users took to the platform to assert they would not pay for blue checkmarks under the new policy, while others announced they would leave the platform entirely.

Nonprofit organizations Human Rights Watch and the NAACP have tweeted they will not be paying for Twitter Blue.

SCOTUSblog, a news website that follows the workings of the US supreme court, said it would cease posting on Twitter entirely. The publication follows a similar move from NPR, the US radio network, which left Twitter last week after being labeled as a “state-affiliated media outlet” under new platform policies.

The removal of free verification processes has also raised concerns about the risk of misinformation and impersonation of legitimate organizations and people. A plethora of false government accounts – including some posing as the US Internal Revenue Service amid tax-filing season – emerged on Thursday. Others changed their account photos and bios to impersonate prominent figures, with a fake Jeff Bezos tweeting he was dissolving Amazon and a fake John McCain tweeting that his plane had crashed (the Arizona senator died in 2018).

Twitter has previously said that government entities could apply for a free blue check through a special program, but some have reported they had thus far been unable to do so. On Thursday, the Bay Area Rapid Transit system, the metro system in the San Francisco Bay Area, where Twitter’s headquarters are located, tweeted it had applied for such a checkmark but had not heard back from the company.

Experts have stated that the failure to verify such entities increases the risks of scams and even threatens to collapse disaster response online, with agencies like the National Weather System now check-less.

Impersonations have been a recurring problem since Musk took over the company. In November, the platform had to pause changes to the subscription program due to an influx of “verified” accounts posing as legitimate users and organizations.