The network intrusion occurred on June 15 and resulted in data being stolen from Enhanced Mobile Satellite Services (EMSS), a system operated by the U.S. Defense Information Systems Agency (DISA) that provides U.S. troops and other DoD employees with global communication capabilities, including data transfers and voice calls.
The stolen data included contact information for about 800 people, like names, titles, email addresses and phone numbers, as well as the identifying numbers (IMEIs) for 34,400 devices, the U.K. National Crime Agency (NCA) said Friday in a press release.
The suspect, whose name and nationality were not released, was arrested Wednesday in Sutton Coldfield, England, as part of a larger law enforcement campaign that targeted cybercrime and resulted in 56 arrests.
According to the NCA, the hacker responsible for the EMSS intrusion published screen shots of the database control panel and a message on Pastebin that read: "We smite the Lizards, LizardSquad your time is near. Were in your bases, we control your satellites. The missiles shall rein upon thy who claim alliance, watch your heads, ** T-47:59:59 until lift off. We're one, we're many, we lurk in the dark,we're everywhere and anywhere. Live Free Die Hard! DoD, DISA EMSS : Enhanced Mobile Satellite Services is not all, Department of Defense has no Defenses."
However, the agency left out of its press release that the message was signed by a group calling itself the ISIS Freedom Fighters.
Lizard Squad is a different hacking group known primarily for launching distributed denial-of-service attacks against online gaming services and making false bomb threats. It has made statements supporting ISIS in the past so it's unclear why the ISIS Freedom Fighters threatened the group in its message.
In January, the Cyber Caliphate, another group of hackers called that claims ISIS affiliation, hijacked the Twitter and YouTube accounts of the U.S. Central Command. The same group later targeted several media organizations.
A recent study from the Brookings Institution, a Washington, D.C., think tank, concluded that ISIS supporters operated at least 46,000 and as many as 70,000 Twitter accounts at the end of last year.