Google CEO Sundar Pichai on Monday became the latest target of hacker group OurMine, which had hacked into Facebook head Mark Zuckerberg’s social media accounts. The group hacked into Pichai’s Quora account and posted messages. One of its later posts read, “Hey, it’s OurMine. We are just testing your security. Please, visit OurMine to upgrade it.”

It became clear that Pichai’s Quora profile, which has 508,000 followers, had been compromised after tweets of his posts on the question-and-answer website appeared on his official Twitter account. However, the Google chief executive, or his team, took over the account within a few hours and deleted the tweets, PTI reported.

OurMine claims it tries to expose security flaws in users’ accounts by hacking into them. “We are just trying to let them know that nobody is safe,” the group told Mic, an online news portal. It had hacked into Zuckerberg’s Twitter and Pinterest accounts earlier this month, after which it broke into the Twitter account of Evan Williams, who is the co-founder and former CEO of the microblogging site.