Part of the stolen data has been published on the internet, as one of the hackers claim, to show that they indeed have something interesting to sell.

A group of hackers, consisting of over 10 people, has hacked the websites of the FBI National Academy Association, an organisation promoting federal and local law enforcement leadership and training at the FBI facility in Quantico, stealing personal records of at least several thousand FBI agents and law enforcement officers, TechCrunch online magazine reported.

The magazine indicated that it knows about at least three websites that were hacked and saw around 4,000 unique records, refusing to give links to either of those citing the sensitivity of the data. The records reportedly contained agents and officers' names, personal and government email addresses, job titles, phone numbers, and their postal addresses.

TechCrunch managed to contact one of the hackers, involved in the websites' breach, who claimed the group actually hacked over "1,000 sites" and stole "over a million data [sic]" on US government employees, not limited to the FBI or law enforcement. The hacker shared that the group is sorting out the data to be sold later, but have already published bits of it as a teaser to show they had something "interesting" on their hands.

READ MORE: German Ministries Hacked, Records of EU-UK, EU-Ukraine Talks Reportedly Stolen

The contact explained that the group used various exploits and out-of-date website plugins to breach them and steal the data, sending TechCrunch several links as proof. One of them led to a subdomain belonging to Taiwan-based electronics manufacturing giant Foxconn.

According to the magazine, the hackers didn't appear worried about the possible danger to the law enforcement agents, whose credentials might be revealed as a result of the hack. The hacker noted that the group did it for "experience and money".

Over a year ago, German magazine Spiegel reported that hackers had managed to steal documents related to EU-UK Brexit talks and records of EU-Belarus, EU-Ukraine talks. The media claimed the hack occurred despite the German intelligence services efforts and that they tracked it to the Turla hacking group, allegedly tied to Russia.