Various Twitter accounts belonging to high-profile users were simultaneously hacked on Wednesday to spread a cryptocurrency scam.

Apple, Elon Musk and Joe Biden were among the hacked accounts. A message from each of these profiles, and many more, was posted promoting a bitcoin wallet address claiming any payment amount sent to that address would be doubled and sent back by the high-profile account owner. This technique is known in cryptocurrency scams.

While there is an investigation underway to find out what happened in the hacking, Twitter’s own account posted what they know about the hacking so far. The tweet read, “We detected what we believe to be a coordinated social engineering attack by people who successfully targeted some of our employees with access to internal systems and tools.”

Twitter first acknowledged the breach on Wednesday afternoon, referring to the situation as a “security incident.” Around 30 minutes later, Twitter noted, “Most accounts should be able to Tweet again. As we continue working on a fix, this functionality may come and go. We’re working to get things back to normal as quickly as possible.”

Before the security breach was addressed, the main blockchain address used on the scam site had collected over 12.5 bitcoin, which is equivalent to around $116,000.

The scammers also changed the emails associated with many of the high-profile accounts they hijacked to make it harder for the real user to regain access.