This is the Guardian.

Today, how did US security files end up in a gaming chat room?

If you're into computer games, then there's a good chance you're on Discord.

Almost 200 million people use this chat room platform to share their play,

message their friends and trade memes.

So it might have seemed like a joke to the teenagers who were part of one Discord group.

When a few months ago, a user called OG started sharing what he claimed was secret US intelligence

files. Hundreds of pages of texts, as well as maps which showed what the US government knew about

the war in Ukraine. The papers were creased and shot in poor light,

though you couldn't miss that many of them carried the emblems of the Department of Defense.

Intelligence officials in the United States are quickly trying to determine the source of leaked

Pentagon documents that reveal key details on the war in Ukraine, as well as intelligence gathering

in Asia and the Middle East. At the Starvade Pearl, the documents were leaked from inside

that private Discord channel and onto the wider internet.

And now the US government has to deal with what's become the biggest security leak in years.

And now the FBI's arrested a suspect.

What's happened isn't just embarrassing for the Defense Department.

These papers reveal secrets that could change the course of the war in Ukraine

and damage the US's relationships with countries around the world.

How could they have spread so easily and wants to stop another leak like this happening?

From the Guardian, I'm Hannah Moore. Today in focus, the Pentagon leaks.

Manisha Gangouli, you're an investigation correspondent at the Guardian and

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