The leader of an online group behind suspected US military document leaks is national guardsman Jack Teixeira, officials have told NBC News.
Teixeira, 21, is said to have overseen a private online group, containing around 30 people, in which the leaked documents were shared.
He is a member of the intelligence wing of the Massachusetts Air National Guard, according to interviews and documents reviewed by The New York Times.
Officials told Sky News’s US partner network, NBC News, that they have been on to him for some time and that an arrest is imminent.
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It comes after US president Joe Biden said he was “concerned” about the widespread leaks, that have rocked The Pentagon.
While their accuracy has been questioned, the leaked documents appear to reveal potential vulnerabilities in Ukraine’s defences, as well as the numbers of UK special forces allegedly active in the country.
Mr Biden said that while he was “concerned” sensitive information had been leaked, “there’s nothing contemporaneous that I’m aware of that is of great consequence”.
He noted there was a “full-blown” investigation by the intelligence community and the US Justice Department. “We’re getting close,” he said, on the probe into what happened.
“But I don’t have an answer.”
Known as “OG” in the Discord chatroom, the suspect behind the leaks allegedly claimed to spend parts of his day inside a secure facility where phones were banned, according to a story published by the Washington Post.
What do the highly classified documents say?
He initially typed up versions of highly secret documents and posted them for the group of about 25 active members from various countries to read, but later switched to posting slews of photos of the documents themselves.
As well as sharing state secrets, OG would also forecast major events before they became headline news, according to another member of the Discord chat interviewed by the Post.
The Pentagon is racing to find the culprit and the scale of the scandal has been compared to the Edward Snowden leaks in 2013.
As more and more of the information contained in the documents is reported, the reach of American intelligence agencies is increasingly under the spotlight.
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According to the New York Times, the documents also illuminate the depth of infighting inside the Russian government.
They paint a picture of feuding behind the walls of the Kremlin over the number of casualties in the Ukraine war.
Officials in several countries have denied or rejected allegations from the leaked records.
Kremlin spokesperson Dmitry Peskov told Sky News: “Like everyone else, we don’t know the degree of authenticity of these documents.
“But even if we disengage from them, long before these documents appeared, we had and still have information that many instructors, including the ones from Britain, and fighters are taking part in the military actions.”