On October 19 local time, according to three people familiar with the matter, the United States is investigating a highly classified intelligence leak about Israel's plan to retaliate against Iran. Previously, an account called "Middle East Observer" posted the top-secret documents on the social platform Telegram ("Telegram") on the 18th, and marked that the documents can only be viewed by the United States and its allies Australia, Canada, New Zealand and the United Kingdom. One of the people familiar with the matter confirmed the authenticity of the documents. A US official said the leak was "deeply concerning".