Billionaires Elon Musk, Jeff Bezos and Bill Gates are among many prominent US figures targeted by hackers on Twitter in an apparent Bitcoin scam.
The official accounts of Barack Obama, Joe Biden and Kanye West also requested 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."
The US Senate Commerce committee has demanded Twitter brief it about the incident next week.
Twitter said it was a "co-ordinated" attack targeting its employees "with access to internal systems and tools".
"We know they [the hackers] used this access to take control of many highly-visible (including verified) accounts and Tweet on their behalf," the company said in a series of tweets.
It added that "significant steps" had been taken to limit access to such internal systems and tools while the company's investigation was ongoing.
The firm has also blocked users from being able to tweet Bitcoin wallet addresses for the time being.