Updated

A pro-ISIS hacker this week pleaded guilty to stealing more than 1,000 military personnel files and sharing them with the terrorist group.

According to the Department of Justice, 20-year-old Ardit Ferizi (a.k.a. Th3Dir3ctorY) admitted to gaining high-level access to an unnamed US company's client list last summer. The Kosovo native provided that data to a member of ISIS, who tweeted the personal details of 1,300 US military personnel in the name of the Islamic State Hacking Division (ISHD).

Ferizi said he did so with the understanding that the group would use it to "hit them [the US] hard."

He was detained in Malaysia in October and waived extradition to the US. Ferizi will be sentenced on Sept. 16 and faces a maximum of 20 years in prison for providing material support to ISIS, and up to five years for accessing a protected computer without authorization and obtaining information. Upon release, he will return to Kosovo.

"Cyber terrorism has become an increasingly prevalent and serious threat here in America, both to individuals and businesses," US Attorney Dana Boente of the Eastern District of Virginia said in a statement. "However, cyber terrorists are no different from other terrorists: No matter where they hide, we will track them down and seek to bring them to the United States to face justice."

In April, The New York Times reported that the US military's Cyber Command is working to disrupt the Islamic State's ability to communicate with one another and potential recruits online. In doing so, it will utilize tools normally reserved for attacks on states like Iran and North Korea. "We are dropping cyber bombs," U.S. Deputy Secretary of Defense Robert O. Work told the Times. "We have never done that before."

In related news, hackers have responded to the Orlando shooting by breaching the Twitter accounts of ISIS sympathizers and militants to post pro-LGBT messages and imagery, Newsweek reports.

This article originally appeared on PCMag.com.