Jeff Bezos, Bill Gates and Elon Musk are among many prominent US figures targeted by scamers on Twitter in an apparent Bitcoin scam.
The official accounts of past US president Barack Obama, Joe Biden and Kanye West also invited donations in the cryptocurrency.
“Everyone is asking me to give back,” a tweet from Mr Gates’ account said. “You send $1,000, I send you back $2,000.”
Twitter said it was a “co-ordinated” attack targeting its employees “with access to internal systems and tools”.
The company said “We know they [the hackers] used this access to take control of many highly-visible (including verified) accounts and Tweet on their behalf”.
The tweet added that “significant steps” were taken by the company to reduce access to such internal systems and tools while the company’s investigation was in process.
Meanwhile, Jack Dorsey, Twitter chief executive tweeted: “Tough day for us at Twitter. We all feel terrible this happened.”
The UK’s National Cyber Security Centre said its invitation officers had “reached out” to the tech firm.
National Cyber Security Centre added in a statement “While this appears to be an attack on the company rather than individual users, we would urge people to treat requests for money or sensitive information on social media with extreme caution”.
One cyber-security expert believed “the breach could have been a lot worse in other circumstances”.
Dr Alexi Drew from King’s College London stated “If you were to have this kind of incident take place in the middle of a crisis, where Twitter was being used to either communicate de-escalatory language or critical information to the public, and suddenly it’s putting out the wrong messages from several verified status accounts – that could be seriously destabilising”.
