Now playing
01:28
Arrest made in hack of U.S. military data
5 ways us can stop hackers orig nws_00010722.jpg
5 ways us can stop hackers orig nws_00010722.jpg
Now playing
01:37
5 ways the US can stop hackers
Now playing
04:21
GPS spoofing: Russia's new cyberweapon?
russia DNC hacking RON 2_00000808.jpg
russia DNC hacking RON 2_00000808.jpg
Now playing
02:30
US blames Russia for power grid cyberattacks
Photo of North Korean leader Kim Jong Un taken from the front page of the state paper Rodong Sinmun on Friday September 22.
Photo of North Korean leader Kim Jong Un taken from the front page of the state paper Rodong Sinmun on Friday September 22.
PHOTO: Rodong Sinmun/KCNA
Now playing
02:28
US blames North Korea for cyberattack
The Kremlin wall and towers dominate the skyline at the Red Square in Moscow, on March 2, 2012. Russia on March 4 votes in presidential elections expected to send Vladimir Putin back to the Kremlin after his four year stint as prime minister.  AFP PHOTO / SERGEI SUPINSKY        (Photo credit should read SERGEI SUPINSKY/AFP/Getty Images)
The Kremlin wall and towers dominate the skyline at the Red Square in Moscow, on March 2, 2012. Russia on March 4 votes in presidential elections expected to send Vladimir Putin back to the Kremlin after his four year stint as prime minister. AFP PHOTO / SERGEI SUPINSKY (Photo credit should read SERGEI SUPINSKY/AFP/Getty Images)
PHOTO: SERGEI SUPINSKY/AFP/AFP/Getty Images
Now playing
03:34
NYT: US spies paid Russian who promised cyberweapons, Trump intel
BERLIN, GERMANY - DECEMBER 28: A participant sits with a laptop computer as he attends the annual Chaos Communication Congress of the Chaos Computer Club at the Berlin Congress Center on December 28, 2010 in Berlin, Germany. The Chaos Computer Club is Europe
BERLIN, GERMANY - DECEMBER 28: A participant sits with a laptop computer as he attends the annual Chaos Communication Congress of the Chaos Computer Club at the Berlin Congress Center on December 28, 2010 in Berlin, Germany. The Chaos Computer Club is Europe's biggest network of computer hackers and its annual congress draws up to 3,000 participants. (Photo by Sean Gallup/Getty Images)
PHOTO: Sean Gallup/Getty Images
Now playing
01:47
NYT: NSA hack bigger than Snowden
A roll of "I Voted" stickers, which are handed out to residents after they vote, sit on an election officials table at a polling place on November 4, 2014 in Ferguson, Missouri.  In last Aprils election only 1,484 of Ferguson
A roll of "I Voted" stickers, which are handed out to residents after they vote, sit on an election officials table at a polling place on November 4, 2014 in Ferguson, Missouri. In last Aprils election only 1,484 of Ferguson's 12,096 registered voters cast ballots. Community leaders are hoping for a much higher turnout for this election. Following riots sparked by the August 9 shooting death of Michael Brown by Darren Wilson, a Ferguson police officer, residents of this majority black community on the outskirts of St. Louis have been forced to re-examine race relations in the region and take a more active role in the region's politics. Two-thirds of Fergusons population is African American yet five of its six city council members are white, as is its mayor, six of seven school board members and 50 of its 53 police officers. (Photo by Scott Olson/Getty Images)
PHOTO: Scott Olson/Getty Images
Now playing
03:15
Homeland Security Chief: Hackers targeting voting systems
PHOTO: CNN/File
Now playing
02:17
Source ties Russia to Wikileaks emails
PHOTO: Reuters
Now playing
02:21
Putin ally warns of 'war' if US elects Hillary Clinton
PHOTO: Getty Images
Now playing
02:30
Hackers playing US for entertainment?
Russian President Vladimir Putin visits a polling station during parliamentary elections in Moscow on September 18, 2016. / AFP / POOL / GRIGORY DUKOR        (Photo credit should read GRIGORY DUKOR/AFP/Getty Images)
Russian President Vladimir Putin visits a polling station during parliamentary elections in Moscow on September 18, 2016. / AFP / POOL / GRIGORY DUKOR (Photo credit should read GRIGORY DUKOR/AFP/Getty Images)
PHOTO: AFP/AFP/AFP/Getty Images
Now playing
02:15
Is hacking group tied to Russian intelligence?
A man walks to use a voting booth March 1, 2016, at one of the Virginia primary election polling stations at Colin Powell Elementary School, in Centreville, Virginia.
Voters in a dozen states will take part in "Super Tuesday" -- a series of primaries and caucuses in states ranging from Alaska to Virginia, with Virginia the first to open its polling stations at 6:00 am (1100 GMT).  / AFP / PAUL J. RICHARDS        (Photo credit should read PAUL J. RICHARDS/AFP/Getty Images)
A man walks to use a voting booth March 1, 2016, at one of the Virginia primary election polling stations at Colin Powell Elementary School, in Centreville, Virginia. Voters in a dozen states will take part in "Super Tuesday" -- a series of primaries and caucuses in states ranging from Alaska to Virginia, with Virginia the first to open its polling stations at 6:00 am (1100 GMT). / AFP / PAUL J. RICHARDS (Photo credit should read PAUL J. RICHARDS/AFP/Getty Images)
PHOTO: PAUL J. RICHARDS/AFP/Getty Images
Now playing
01:52
US officially blames Russia for political hacks
FBI Director James Comey (R) speaks as Assistant Attorney General for National Security John Carlin (L) listens during a news conference for announcing a law enforcement action March 24, 2016 in Washington, DC.
FBI Director James Comey (R) speaks as Assistant Attorney General for National Security John Carlin (L) listens during a news conference for announcing a law enforcement action March 24, 2016 in Washington, DC.
PHOTO: Alex Wong/Getty Images
Now playing
04:31
Assistant attorney general to hackers: We'll find you
Hillary Clinton and Donald Trump shake hands following the first presidential debate moderated by NBC host Lester Holt(bottom L) at Hofstra University in Hempstead, New York on September 26, 2016.
Hillary Clinton and Donald Trump shake hands following the first presidential debate moderated by NBC host Lester Holt(bottom L) at Hofstra University in Hempstead, New York on September 26, 2016.
PHOTO: PAUL J. RICHARDS/AFP/Getty Images
Now playing
01:27
Fact check: Was Russia behind the DNC cyberattacks?
WESTBURY, NY - SEPTEMBER 26:  Democratic presidential nominee Hillary Clinton speaks during a debate-watch party at The Space at Westbury on September 26, 2016 in Westbury, New York. Tonight was the first of four debates for the 2016 election - three presidential and one vice presidential.  (Photo by Justin Sullivan/Getty Images)
WESTBURY, NY - SEPTEMBER 26: Democratic presidential nominee Hillary Clinton speaks during a debate-watch party at The Space at Westbury on September 26, 2016 in Westbury, New York. Tonight was the first of four debates for the 2016 election - three presidential and one vice presidential. (Photo by Justin Sullivan/Getty Images)
PHOTO: Justin Sullivan/Getty Images North America/Getty Images
Now playing
01:50
Clinton's Wall Street speeches leaked?

Story highlights

NEW: Relative provides lengthy narrative asserting suspect's innocence, says family is "shocked"

Kosovo citizen Ardit Ferizi is accused of stealing personally identifiable information of U.S. military members

A criminal complaint alleges he hacked into a computer system and gave the information to ISIS

(CNN) —  

Authorities have arrested a Malaysia-based hacker who they accuse of stealing personal information of U.S. military members and giving it to ISIS.

Ardit Ferizi, a Kosovo citizen, was detained in Malaysia on a provisional U.S. arrest warrant alleging he provided material support to ISIS and committed computer hacking and identity theft, the U.S. Justice Department said.

According to a criminal complaint, Ferizi hacked into the computer system of a company in the United States and stole personally identifiable information of more than 1,000 U.S. service members and federal employees. Then, he allegedly gave that information to several ISIS figures, including a prominent propagandist for the group, the complaint says.

Ardit Ferizi
Ardit Ferizi
PHOTO: from facebook

U.S. Assistant Attorney General John Carlin called the case against Ferizi – which combines cybercrime and terror charges as U.S. authorities aim to step up their crackdown on ISIS – “a first of its kind.”

This arrest demonstrates our resolve to confront and disrupt ISIL’s efforts to target Americans, in whatever form and wherever they occur,” Carlin said in a statement. ISIL is another name for the Islamic extremist group ISIS.

Ties to prominent ISIS propagandist

The criminal complaint alleges there’s probable cause to believe Ferizi hacked into a server and stole names and personally identifiable information of more than 1,300 U.S. military and other government personnel – a list that was later posted online in August by a group calling itself the “Islamic State Hacking Division.”

“We are extracting confidential data,” a message from the group said, according to the complaint, “and passing on your personal information to the soldiers of the khilafah, who soon with the permission of Allah will strike at your necks in your own lands!”

The military members’ data, including home addresses and photos, was allegedly stolen by Ferizi and passed on to Junaid Hussein, a British hacker who was active on social media recruiting Westerners to join ISIS, authorities said.

The U.S. military announced in August that it had killed Hussein in an airstrike in Syria. He was a leading member of ISIS’ so-called CyberCaliphate, which has carried out mostly nuisance hacks on military and other government websites in the United States, France and other countries.

After the list’s publication in August, Pentagon officials said they were investigating.

“I take it seriously, because it is clear what they are trying to do,” Gen. Raymond Odierno, the U.S. Army chief of ctaff, said at the time.

Many of the phone numbers and email addresses on the list were not in service when tested by CNN in August. But one person on the list, reached by phone, confirmed he had previously served in the U.S. military. He asked not to be named, but said he had recently been notified by the Pentagon that his name and personal information were on the list. Another, reached by email, confirmed she was a government employee who had been warned by the military about being on the list.

Relative: Family is ‘shocked’ by charges

According to the complaint, Ferizi is believed to be the leader of a hacking group known as Kosova Hacker’s Security.

A relative of Ferizi provided CNN with a recent narrative of Ferizi’s life and added that the family was “truly surprisingly shocked” to hear of the accusations tying Ferizi to ISIS.

The family is very skeptical of the charges, and the news has been very painful for the family, especially Ferizi’s mother, the relative said.

The family member went on to tell CNN that Ferizi’s relatives have no ties to ISIS or any criminal organization, and that they “love the USA for what they did in Kosovo, helping my family and my people.”

When Ferizi was age 15, he ran into some problems with the police for allegedly hacking a “news portal,” the relative said.

But the family wasn’t aware “of his title ‘hacker,’ but we knew that he had good skills in computer science and that’s why (a family member) invested in him to cultivate his talents even more,” the relative said.

Why Kosovo students go to Malaysia

Ferizi moved to Malaysia to study computer science because of its schools and their expertise. It’s not easy for Kosovo students to get into schools in the European Union or the United States, the family member said.

Other students from Ferizi’s hometown in Kosovo also attended the same technical school as Ferizi did, the relative added.

Malaysian police said the 20-year-old alleged hacker had entered the country in August 2014 to study computer science and computer forensics at a college in Kuala Lumpur.

Ferizi was arrested while on his way home to Kosovo from Malaysia on September 15, the relative said. The family paid for his ticket to come home because, the relative claimed, Ferizi has mental health issues and he complained to his family that they were worsening so he dropped out of university to return home.

“We were waiting for his return, then suddenly this happened,” the family member said.

The family spoke to Ferizi twice while he was in custody with the help of a Malaysian human rights group called Suaram. Both times Ferizi told them he was being accused of being in Syria in 2013, the relative said.

Questions about Syrian travel

The family handed over his old passport to investigators, and the passport contained a stamp for a four-day trip to Turkey in 2013 when Ferizi was 17. He went there with his mother and father to attend a trade fair in Istanbul, according to the relative.

The family was shocked that authorities would pressure Ferizi so much over a four-day trip to Turkey with his parents, the relative said.

The relative spoke with Ferizi on September 23 and then again on October 3 and during the brief conversations, Ferizi said that Malaysian authorities were pressing him hard on whether he traveled to Syria. Ferizi was becoming so tired that he “may accept what they are saying just to come home to Kosovo,” the relative said.

Ferizi’s family member has been unable to contact him since but said if the court would recognize that he is mentally ill and release him to his family, they could take care of him.

Malaysian authorities had been monitoring Ferizi for a few months after receiving information from the FBI, said Sr. Assistant Commissioner Datuk Ayob Khan Mydin Pitchay, head of the counterterrorism division, Special Branch of the Royal Malaysian Police.

Ferizi was arrested September 15 in Kuala Lumpur, the assistant commissioner said. He is under remand under a provisional arrest warrant while U.S. authorities apply for his extradition.

CNN’s Joshua Gaynor, Dugald McConnell, Brian Todd, Chan Kok Leong, Vivian Kam and Michael Martinez contributed to this report.