WASHINGTON — The Malaysian authorities have arrested a 20-year-old man who the Justice Department said Thursday ran an Internet hacking ring in Kosovo that provided stolen personal information of more than 1,300 American service members to the Islamic State.

In a complaint unsealed in federal court in Northern Virginia on Thursday, the Justice Department alleged that the Kosovar, Ardit Ferizi, hacked into the server of a company based in the United States, stole the personal information and gave it to the Islamic State to use against the service members.