One of the largest leaks of alleged classified US military documents in a decade has sparked an official investigation by the Department of Defence and could complicate American support for Ukraine shortly before a major offensive by Kyiv.
Several tranches of documents have appeared on social media in recent weeks, some of them reportedly intended only for those with the highest levels of US security clearance.
The information covers a wide range of topics, from US assessments of the war in Ukraine to intelligence gathered on diplomatic allies.
Here’s what we know about the leaks so far:
What is in the documents?
According to The New York Times and other outlets, the initial document leaks focused on US assessments of the war in Ukraine originally written in February and March, including estimated casualties on both sides and what equipment and ammunition would be required by Kyiv in the future.
However, they reported that at least one document appears to have been altered to lower Russia’s death toll in the war and inflate that of Ukraine, raising questions over the reliability of the papers.
The documents also reportedly lay out the US’s extensive access to intelligence from inside Russia’s government, revelations that could have dire consequences for American espionage going forward.
National Security Council spokesman John Kirby said some of the documents were fake.
"We know that some of them have been doctored. I won't speak to the validity of all the documents," he told reporters.
Where did the documents appear?
The leaked information has turned up on several social media platforms and apps in recent weeks, including Twitter and YouTube.
Bellingcat, an independent investigative news outlet, said the documents appeared to have originally been posted on obscure internet sites, including a Minecraft channel on Discord, which is a popular messaging application for fans of computer games.
The documents drew greater attention once they were discovered and posted more broadly to far-right noticeboard 4Chan and pro-Russian messaging groups on the Telegram app.
What do we know about their origins?
Most of the documents appear to be photographs of classified Pentagon briefing reports that look as though they had previously been folded up before the images were taken, according to the Times.
That suggests someone removed them, possibly in a pocket or briefcase, from their original home.
If they are real, the key question is who leaked them — and no one has the answer.
The method of circulation suggests they were removed by an American, although that has not been confirmed. While the US government has not officially confirmed their authenticity, CNN reported on Sunday that an official investigation had been opened into their origin by the US Department of Justice.
Have they been deleted from the internet?
With the documents now widely shared on the internet, it is highly unlikely that they can now be removed or hidden.
At least one major social media platform, Twitter, seems to have little appetite for forcibly erasing the documents. Still, the White House said efforts were being made to remove the material.
How have countries responded?
Ukraine has dismissed the documents publicly as Russian disinformation, with an adviser to President Volodymyr Zelenskyy telling The New York Times that they were “fictional”.
At the same time, Russian state media Sputnik claimed the leak exposed divisions in the US over President Joe Biden’s Ukraine policy, while a government spokesman told CNN the documents showed the close involvement of the US in the war in Ukraine.
US allies have so far reacted with concern to the news of the leaks, but have emphasised their faith in American authorities to investigate.
The South Korean government, which was mentioned in the leaks, said in a statement on Sunday it would be discussing the matter with the US, while Australia’s Department of Foreign Affairs and Trade told the ABC it was seeking “further information”.