A Malaysia-based hacker who stole the personal information of military veterans and active duty Americans was arrested. According to a provisional U.S. arrest warrant, this man sent the stolen data to Islamic State agents.

Originally hailing from Kosovo, Ardit Ferizi hacked a U.S. contractor and stole the personally identifiable information (PII) of 1,000 military members and federal employees. He passed the information along to ISIS, including to Junaid Hussein, a British-born propagandist recently killed in an American airstrike.

PII refers to any data that can be used to identify a specific person, such as a social security number, military rank or home phone number. When this information is in a cyberterrorist’s hands, it becomes far easier to impersonate a hacked user online. The data Ferizi stole included home addresses and photos. The people victimized by the hack have already been notified by the Pentagon.

Ferizi’s combination of cybercrime and terrorism was called “the first of its kind” by U.S. Assistant Attorney General John Carlin.

“This arrest demonstrates our resolve to confront and disrupt ISIL’s efforts to target Americans, in whatever form and wherever they occur,” Carlin said.

Ferizi was arrested in Kuala Lampur on Sept. 15 and is currently being provisionally jailed until the U.S. can extradite him.