OurMine, a hacking group that made a name for itself attacking high-profile celebrities and business people, said that it hacked WikiLeaks on Thursday and redirected it to a page it had created. According to The Verge, which saw the page, OurMine said that its hack was a response to a challenge it faced from WikiLeaks.

“Hi, it’s OurMine (Security Group),” the webpage read, “don’t worry we are just testing your…. blablablab, oh wait, this is not a security test! Wikileaks, remember when you challenged us to hack you?”

WikiLeaks has become a prominent source of information on everything from wars to climate change. The site, which was founded by Julian Assange, has also been a lightning rod of controversy, with some saying that it exposes important truths about the world, and others saying it puts people in undue danger.

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OurMine has come on the hacking scene in rather short order and last year hacked several prominent technology executives, including Facebook CEO Mark Zuckerberg, Google CEO Sundar Pichai, and others. After hacking accounts, OurMine often says that its efforts were aimed at “testing” the security of the victim. OurMine has also targeted companies, like HBO, as recently as this month.

According to The Guardian, the apparent hack on WikiLeaks might not have been an outright break-in into the site’s servers, allowing OurMine access to sensitive information. Instead, the group might have used a technique called “DNS poisoning” that duped the Internet into thinking wikileaks.org was actually hosted on a server controlled by OurMine. Once it was fixed, WikiLeaks was brought back. And as of this writing, WikiLeaks is back up and running.

WikiLeaks responded to the attack earlier this morning, saying that its “servers have not been hacked.” It reiterated in a follow-up tweet that its servers being hacked is a “fake new (sic) story.” WikiLeaks, however, did not address OurMine by name.

OurMine hasn’t publicly commented since the attack.