Jack Teixeira, a serving US Air National Guard, has been charged with carrying out the most serious leak of US intelligence documents in 10 years.
The Pentagon has called the leaks the most serious national security breach in years but Teixeira appears to have allegedly leaked the documents to discuss them with friends rather than for ideological or espionage reasons.
Here's everything we know about Jack Teixeira.
Where did Jack Teixeira share the documents?
It is believed Teixeira began sharing the documents in a Discord channel he ran called Thug Shaker Central.
Discord is a computer progamme and mobile app that is popular with gamers and allows people to join private chat rooms that allow people to communicate via voice, webcam or written messages.
Teixeira's group drew roughly two dozen enthusiasts who talked about their favourite types of guns and also shared memes and jokes.
It has also been reported some of the memes were racist.
The group also held a running discussion on wars that included talk of Russia’s invasion of Ukraine.
Teixeira was known as "the OG" leader of the group and is believed to be older than most of the users who are mostly teenagers.
Teixeira also reportedly commented regularly on his Christian faith in the group, with some members occasionally praying together digitally.
In interviews with members of the group carried out by the FBI and journalists they reported Teixeira originally began copying the documents in text format.
But according to the Associated Press (AP), he allegedly eventually started taking photos of the documents and posting the image in Discord because he was annoyed other users weren’t taking him seriously.
The Justice Department has not alleged a particular motive. Accounts of those in the online private chat group where the documents were disclosed have depicted Teixeira as motivated more by bravado than ideology.
What was Jack Teixeira's job?
Teixeira’s speciality in the Air National Guard was as a "cyber transport systems specialist," essentially an IT specialist responsible for military communications networks, including their cabling and hubs.
In that role, Teixeira would have had a higher level of security clearance because he would have also been tasked with the responsibility to access and ensure protection for the network, a defence official told AP.
While he was enlisted, Teixeira opposed many of the priorities of the US government and denounced the military "since it was run by the elite politicians," a member of the group told AP.
They said: "He expressed regret (about) joining a lot."
But the person has stressed that he didn’t believe Teixeira leaked documents to undermine the US government or for an ideological reason.
How did the FBI find Teixeira?
The FBI had been honing in on Teixeira for days, but it appears three keys pieces of information led them to him.
Firstly Discord provided the FBI with billing receipts and cooperation with their investigation.
It is understood Teixeira was the leader of his Discord group with the programme offering a paid service to offer extra enhancements for their chatrooms.
Want a quick and expert briefing on the biggest news stories? Listen to our latest podcasts to find out What You Need To Know
Teixeira also used his government computer to search for the word 'leak' last week when news media reports revealed that classified documents had been improperly disclosed.
The FBI also spoke to a member of the Discord group that told them a username linked to Teixeira began posting what appeared to be classified information roughly in December in an online forum meant for the discussion of geopolitical affairs and past and current wars.The person provided the FBI with basic identifying information about Teixeira, including that he called himself "Jack," claimed to be part of the Air National Guard and appeared to live in Massachusetts, according to documents released in court on Friday.
A member of the Discord also alleged to AP this week that Teixeira knew the FBI was looking for him.