Several prominent Twitter accounts appear to have been hacked Wednesday, including those of musician Kanye West, tech luminary Elon Musk and US presidential contender Joe Biden.
The accounts of former President Barack Obama, Amazon owner Jeff Bezos, financier Warren Buffet and former New York City Mayor Michael Bloomberg were also affected.
Screen grabs taken from the accounts appear to show them posting a link asking for Bitcoin donations, variously saying in some form they are "giving back" to their communities or fans by doubling any donations.
Twitter's official support account said the microblogging website is "aware of a security incident impacting accounts on Twitter."
"We are investigating and taking steps to fix it. We will update everyone shortly," it said.