Breaking tonight, U.S. troops killed in the Middle East with a new round of missile strikes

and new word from the president on how long this operation could last.

What we're learning about the deaths of American service members as you see smoke rising from explosions hitting the heart of Tehran.

In Israel, casualties reported as Iran fires back.

Today, these newly released videos from the U.S. military, more missile launches from a Navy

ship and strikes on key Iranian facilities.

Tonight, President Trump telling NBC News Operation Epic Fury is ahead of schedule and posting

this video.

We agree for the true American patriots who have made the ultimate sacrifice, and sadly,

there will likely be more before it ends.

His new warning to Iran retaliating tonight, hitting beyond Israel, targeting other Gulf nations.

And the question, who will lead Iran with the Ayatollah and dozens of other leaders now dead?

Plus, Iran threatening to cut off the world's oil supply, this tanker on fire at sea, what it could all mean for the price of your gas.

And passengers left stranded as airports across the Middle East shut down, the travel chaos around the world.

Then, with the fighting escalating tensions here at home.

The FBI investigating possible terror connections to a deadly

mass shooting in Texas. Could it have anything to do with the Iranian strikes? Our special coverage

on Nightly News starts right now. This is NBC Nightly News with Hallie Jackson.

Good evening.

We begin tonight in the Middle East and new video today of another round of strikes in Tehran.

You see it there.

We're learning now that three American service members have been killed in this operation to attack Iran with President Trump late tonight,

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