The messages contained racial epithets, and included a retweet of a message supporting Nazi Germany.
Hezbollah leader: Israeli drones will be downed
A spokesman for Lebanon's Hezbollah says two Israeli drones crashed in Beirut without the militant group firing on them. He said it was the first clear risky breach of rules of engagement since the two sides fought a month-long war in 2006.
Twitter users, of course, responded as they typically do - a mix of sarcasm and jokes while being questionably concerned. If the CEO of Twitter can be compromised in such a way, then so too could the accounts of world leaders.
It is still unclear how these individuals got access to Jack's account nor, if they still do have control his Twitter.
The tweets have since been deleted, and Twitter has released a statement about the incident.
Twitter has a two-factor authentication process for users looking to add extra security to their profile.