Where did leaked U.S. secrets appear? On a chat app popular with gamers.

As the U.S. government hunts the source of an online leak of classified military documents, public attention has turned to a chat app popular among gamers, including a forum for a YouTuber named wow_mao.

The documents, which were shared on the Discord app last month and spread to other corners of the internet, appear to detail Ukrainian and Russian military capabilities and offer a look at American intelligence gathering on other countries, The Washington Post has reported.

In the overlap between internet meme culture and U.S. military secrets, some have traced the spread of the documents to Discord servers, which are similar to chatrooms, with names including Minecraft Earth Map, the End of Wow Mao Zone and Thug Shaker Central.

Defense Secretary Lloyd Austin vowed Tuesday to “turn over every rock until we find the source of this” and said he was informed of the leak in early April. Yet, photographs of pages of documents, which seemed printed and folded together, appeared to have sprung up weeks earlier on Discord, and several were then posted on Telegram and Twitter, The Post reported.

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