WikiLeaks has dismissed claims its servers were hacked Thursday by the OurMine hacking group, following online suggestions that the whistleblowers’ homepage had been defaced with the words ‘Hacked by #OurMine.’

Some WikiLeaks users reported seeing the site’s homepage defaced with text apparently from the OurMine group, which has carried out recent hacks on Youtube, Mark Zuckerberg, Buzzfeed, and others.

WikiLeaks servers have not been hacked. — WikiLeaks (@wikileaks) August 31, 2017

“Hi it’s OurMine (Security Group),” the text continues, “WikiLeaks, remember when you challenged us to hack you? Anonymous, remember when you tried to dox us with fake information for attacking wikileaks?”

“There you go! One group beat you all,” it said.

OurMine is largely seen as a ‘white hat’ hacking group, meaning its exploits focus on exposing vulnerabilities in websites rather than malicious attacks. However, its Buzzfeed hack was revenge for publishing an article claiming to expose the identity of one of its members.

The hack by OurMine was likely carried out on WikiLeaks’ Domain Name System (DNS) records on its domain name (www) server.

This means it wasn’t WikiLeaks’ own servers (containing its important files) that were hacked. Although technically hacked, it did not endanger WikiLeaks’ own servers or put at risk its whistleblowing efforts.

DNS is a naming system that converts website addresses (www.etc.com) to IP addresses for computers to read. The hijack likely made the site’s DNS records point browsers seeking WikiLeaks to a site on a server owned by OurMine.

WikiLeaks severs have not been hacked. There have been two types of internet infrastructure (DNS) attacks. Always use HTTPS or our .onion. — Julian Assange 🔹 (@JulianAssange) August 31, 2017

Julian Assange tweeted “There have been two types of internet infrastructure (DNS) attacks. ALways use HTTPS or our .onion.

OurMine released a statement explaining its hack on WikiLeaks. “We did that because they challenged us to hack them about a few months ago, and we’ve been working on this hack for a very long time, and finally we did it!”

The statement also said it had access to new messages sent to WikiLeaks’ press email.