Kim Vinnell

They're now under siege.

Trump's announcement of Khamenei's death thrusts the country into levels of uncertainty not seen since the 1979 revolution.

The supreme leader wielded final authority over the military, the judiciary, the media, and Iran's powerful Revolutionary Guard.

Iran is now in open warfare, and its people are being urged by the U.S.

president to revolt.

With Khamenei gone, there is an immediate power vacuum in Iran, but it isn't yet clear who will fill it.

Over the past two weeks, the CIA has been sharing intelligence with senior U.S.

officials, briefing them on potential replacements.

Erin Banco in Washington, D.C., has the story.

Erin says other options include other hardline figures or, less likely, an opposition leader.

But she says whoever takes over, officials in the U.S.

don't expect any major change in Iran's policy.

The large-scale attack on Iran could be the riskiest and most consequential move of Trump's second term.

It marks a pivot from quick contained operations like last month's raid in Venezuela to what experts warn could become a drawn-out conflict with Iran and a wider regional war.

So why did President Trump do this?

Well, national security reporter Phil Stewart has uncovered exclusive details about the briefings the president received ahead of the attack.

How far Trump will go for those rewards remains to be seen.

As Phil says, we've seen dramatic events unfolding hour by hour on what's become a momentous day in Middle Eastern history.

Iranians throughout the country woke to the sound of bombs exploding and fighter jets overhead.

People were watching from rooftops as cars, trees and buildings burned below.