On Monday, a White House spokesperson said President Biden was "deeply concerned" about the unauthorized release.

The FBI announced Tuesday it was investigating the alleged leak of classified US intelligence documents about Israel's plans for a retaliatory strike on Iran.Iran has been bracing for a response since it unleashed a wave of close to 200 ballistic missiles on Israel on October 1 in retaliation for the killings of Tehran-backed senior figures in Hamas and Hezbollah.

The FBI has opened a federal investigation over the leak of top secret U.S. intelligence documents regarding Israel's preparation for an attack against Iran. Why it matters: The leak was one of the most serious security breaches within the U.S. intelligence community in years.