An unknown hacker on Sunday posted the details of almost 10,000 Department of Homeland Security (DHS) employees online, which he claimed to obtain by hacking the Justice Department.
The hacker, who tweets from the account @DotGovs, is now threatening to dump the information of 20,000 FBI employees on Monday.
The DHS database appears to be genuine. Ahead of the dump, the hacker shared the information with Motherboard, which conducted a spot check of the database and found most of the entries matched up.
The hacked DHS database includes individuals listed as everything from contractors and special agents to intelligence analysts and technicians.
An agency spokesman said the DHS is looking into the purported disclosure but that "there is no indication at this time that there is any breach of sensitive or personally identifiable information."
Motherboard reports that the FBI database, which the hacker leaked to the publication with the DHS trove, also appears to be genuine.
The hacker told Motherboard that he obtained the data by first compromising a Department of Justice email account. He declined to elaborate how he gained access to the account.
When he was unable to log into a Justice Department web portal using the stolen credentials, he simply called the relevant department and asked for help.
“So I called up, told them I was new and I didn't understand how to get past [the portal],” the hacker told Motherboard. “They asked if I had a token code, I said no, they said, ‘That's fine — just use our one.’ ”
Using that, he says he was able to access an online virtual machine that was responsive to the already-hacked email credentials. That allowed him to gain access to the work computer of the email account owner.
The hacker claims the databases were on a Justice Department intranet and that he had access to a full terabyte of information — although he says he was only able to download 200 gigabytes of data.
Tweets from the @DotGovs account suggest that the hack was motivated by support for Palestine.
“When will the US government realize we won't stop until they cut relations with Israel,” the account tweeted on Sunday.
“Be sure to tweet #FreePalestine to bring awareness to all the kids dying by Israeli bombs that the US government funds!” it tweeted earlier that day.
Some of the tweets suggest that there is more than one person manning the account.
Another group of hackers, known as Crackas with Attitude, have recently broken into the personal email accounts of several high-ranking law enforcement and intelligence officials to demonstrate support for Palestine.
In the last six months, the teenaged hackers have infiltrated personal accounts belonging to CIA Director John Brennan, Director of National Intelligence James Clapper, Secretary of Homeland Security Jeh Johnson and FBI Deputy Director Mark Giuliano. Most recently, they targeted President Obama’s senior advisor on science and technology, John Holdren.
The group portrayed themselves in an interview with The New York Post late last year as being motivated by opposition to U.S. foreign policy and support for Palestine.
In a series of tweets in November, the group’s leader, Cracka, posted graphic images of violence apparently taken in Israel.
“[D]o you understand what i was fighting for now?” he tweeted.
“[F]or other countries, you all knew i risked my life for palestine, for freedom for others, for rights for other people,” he tweeted.
“John and Jeh are both very big people and high-ranking people, so, I mean, if we hacked them, they would be ashamed," Cracka told CNN. “But it was really because the government are killing innocent people, they also fund (Israel) for killing innocent people.”
Updated 12:10 p.m.