U.S. officials are extremely concerned about a potentially major security breach after two alleged U.S. intelligence documents about Israel's preparations for an attack on Iran were published by a Telegram account affiliated with Iran.

Why it matters: The alleged leak comes as Israel completes weeks of preparations for a retaliation against Iran, which attacked Israel with a barrage of ballistic missiles on Oct. 1.

• The leak could be an attempt to disrupt the Israeli operation.
• The Pentagon and the Office of the Director of National Intelligence declined to comment on the leaked documents, but did not dispute their authenticity.