Anonymous claims it has hacked the FBI, uploading email addresses and personal information relating to the current director to online storage site Pastebin.
The information, posted by user Black-Shadow of the Slovenian branch of the hacktivist group, purportedly contains FBI domain email addresses and passwords for 68 agents, although the user claims in his post that the collected log-in details are "not all ours".
The post also includes a short profile on FBI director James Brien Comey Jr, including sensitive information such as his date of birth, his wife's name, the date they got married, his educational history and even the geographical coordinates of his residence.
Two internal FBI websites are also included in the post – the FBI's Virtual Academy website from its training division, and the FBI Agents Association, which claims to be a non-governmental agency set up "for active duty FBI agents striving to protect and advance the interests of agents both within the Bureau, as well as in the public domain".
The information file states that two of the FBI's domain name servers for its website www.fbi.gov were targeted, and the hackers were able to attack and access information from seven open ports on the servers.
Anonymous Slovenia posted the Pastebin link on its Facebook Page, along with the comment "Laughing at your security".
IBTimes UK has contacted the FBI for comment and is awaiting a response. Anonymous Slovenia has declined to comment.
Anonymous has previously been on the front pages of newspapers around the world for cyber-attacks against high profile targets such as the CIA, Sony and the UK's Serious Organised Crime Agency in 2012.
In an interview with IBTimes UK in August 2013, one prominent member of Anonymous in the UK admitted that there was a lot of infighting within the group and that this made it more difficult to be taken seriously.