(Newser) – That's got to be embarrassing. Twitter CEO Jack Dorsey—the man who sent the world's first tweet—had his Twitter account hacked Saturday, Engadget reports. The hacker group OurMine posted a few videos to Dorsey's account followed by a tweet reading, “Hey, it’s OurMine, we are testing your security” and a link to its website. According to the Hill, OurMine pretends it's doing security checks then charges victims thousands of dollars to get control of their accounts back. It's recently hit other tech CEOs, including Mark Zuckerberg. OurMine reposted their message to Dorsey's Twitter account every time it was deleted before apparently losing access to the account after an hour or so. It seems the hackers were able to access Dorsey's Twitter through his Vine account, but exactly how they got his password is unknown. (Read more Twitter stories.)