Fake account users are taking advantage of Twitter's new paid verification policy to impersonate public figures, including George W Bush and Tony Blair.
Previously, the company granted verification to people it deemed to be high-profile and at risk of impersonation, such as politicians, celebrities or journalists, by showing a blue tick symbol next to their user name.
But Elon Musk, who purchased the company two weeks ago for $44 billion, updated the premium version of the product to award all paying subscribers with same blue check mark that government, celebrity and business accounts are given free to confirm their identities.
Once the option was available, users started creating accounts in the name of major brands and politicians, potentially jeopardising Twitter’s now-shaky reputation with advertisers.
One account with a blue tick appeared to show former US president George W Bush tweeting “I miss killing Iraqis” with a sad-face emoji, according to screenshots circulating online.
The images showed the post retweeted by another false account claiming to be former British prime minister Tony Blair. Both had been deleted by the time of writing.
More confusion arose after the company appended grey check marks to accounts that had been verified under the old rules, then removed them when Mr Musk changed his mind.
The legacy check marks will be removed in “coming months,” Mr Musk said in a tweet on Thursday, unless people pay for an $8 a month Twitter Blue subscription.
He said there were too many “corrupt” verification marks and there was no choice but to phase out the old ones.
An account impersonating Nintendo tweeted an image of the Super Mario character swearing. One posing as the pharmaceutical brand Eli Lilly & Co tweeted that insulin was now free.
“We apologise to those who have been served a misleading message from a fake Lilly account,” the official account tweeted.
Even Twitter is not immune from impersonation. One account which had purchased the new blue check gained tens of thousands of retweets by pretending to be the social media company's official account and telling followers that Twitter Blue would be free.
“Over the next few days, the absolute top priority is finding and suspending any verified bots/trolls/spam,” Mr Musk wrote in an email to staff on Wednesday night viewed by Bloomberg.
Twitter’s trust and safety team spent Thursday morning focusing on the most high-profile of the instances, but after a spate of layoffs could only deal with impersonators of the highest profile accounts, people familiar with the matter said.
The team had no means to deal with fraud related to legacy verified accounts, such as those for journalists, with smaller followings, they said.
Later on Thursday, Yoel Roth, the company’s head of trust and safety, resigned, they said. Mr Roth was one of the most visible executives gaining power under Mr Musk, as he took to Twitter to explain the company’s shifting policies.
A member of the trust and safety team at Twitter said the unit’s future was unknown, and that Mr Roth had been acting as an advocate and a shield for the group — and appeared to have been in Mr Musk’s good graces.
Employees who had reported directly to Mr Roth met to discuss the blue check mark problem shortly after Mr Musk made his first address to employees, telling them that bankruptcy was possible if the company did not start generating more cash, the people said.
Bloomberg contributed to this report