What happened?
Early in the afternoon (Eastern time) on July 15th, a hacker -- or hackers -- gained control of a series of Twitter accounts owned by Bitcoin enthusiasts, executives and exchanges. Upon gaining control of those accounts, the hackers tweeted messages to those accounts' audiences claiming that they would be "giving 5000 BTC back to the community" and directing users to cryptoforhealth.com. People who visited the now-defunct website were told that if they sent Bitcoin to a specified address, they would receive double the amount in return, plus a bonus if contributions exceeded a certain threshold.

After the hackers had spread the message from multiple Bitcoin-related Twitter accounts, they went big. The first major account to be breached appears to be Elon Musk's, followed in short order by Bill Gates, Uber, Apple, Kanye West, Jeff Bezos, Mike Bloomberg, Joe Biden and former president Barack Obama, 

Most of these accounts tweeted some variant of the same message: If someone were to send Bitcoin to the address specified in the tweets during a 30-minute window, the account owner would return double the amount. These outsized claims succeeded in tricking some people into sending over valuable cryptocurrency, but no crypto was ever sent in return. (Obviously.) All of the tweets sent from these high-profile accounts directed victims to the same Bitcoin address.

By this point, Twitter had caught on and was attempting to contain the account breaches. In an effort to prevent more scammy messages being shared, Twitter temporarily removed the ability for verified users to tweet. If the owners of those accounts wanted to communicate on the platform, they either had to create temporary accounts, retweet existing tweets, or both. (Meanwhile, non-verified Twitter users basically had a field day.) Twitter appeared to get the situation under control and restored verified users’ ability to tweet at around 8:30 PM Eastern.