Iran live updates: 7th killed service member is identified

The top U.S. commander in the Middle East said the U.S. has "severely degraded" Iran's air defenses, destroying hundreds of Iran's ballistic missiles, launchers and drones.

"In simple terms: We're focused on shooting all the things that can shoot at us," Admiral Brad Cooper said in a video update on the operation released Tuesday.

Cooper said the U.S. has also destroyed 17 Iranian ships, including an Iranian submarine.

More than 50,000 troops are participating in the operation, which has so far struck nearly 2,000 targets in Iran, he said.

"Many of you may remember the Shock and Awe strikes of 2003. The first 24 hours of this operation were nearly doubled the scale," he said.

Cooper referenced the first U.S. use of one-way drones, saying, "I'd like to point out these drones were originally an Iranian design. We took them back to America, made them better and fired them right back at Iran."

Cooper said the U.S.' combat power is "building" while Iran's is "declining."

"My overall operational assessment is that we are ahead of our game plan," he said.

More than 9,000 Americans have returned from the Middle East since the launch of the joint U.S.-Israeli strikes on Iran, according to President Donald Trump.

This number reflects Americans who left on their own volition in recent days without the State Department assistance that is now being offered.

Trump said in a social media post that if there are other U.S. citizens who wish to return home from the region, they should register with the State Department.

"The Department will identify where you are, and provide travel options to you," Trump said. "We are already chartering flights, free of charge, and booking commercial options, which we expect will become increasingly available as time goes on."

The Pentagon on Tuesday identified four of the six American troops killed in the opening hours of the war with Iran.

The Pentagon on Tuesday identified four of the six American troops killed in the opening hours of the war with Iran.

Capt. Cody A. Khork, 35, of Winter Haven, Florida; Sgt. 1st Class Noah L. Tietjens, 42, of Bellevue, Nebraska; Sgt. 1st Class Nicole M. Amor, 39, of White Bear Lake, Minnesota; and Sgt. Declan J. Coady, 20, of West Des Moines, Iowa, died Saturday in Kuwait from an Iranian drone attack.

All soldiers were assigned to the 103rd Sustainment Command, an Army Reserve unit based in Des Moines, Iowa.

READ MORE | Pentagon IDs 4 American troops killed in Kuwait

Iranian clerics have issued fatwas calling on Muslims worldwide to avenge the killing of Ayatollah Ali Khamenei during the U.S.-Israeli attack on Iran, the Department of Homeland Security said in a "Critical Incident Note" obtained by ABC News.

The first fatwa was issued on Sunday by Grand Ayatollah Naser Makarem Shirazi and said avenging Khamenei's death "is the religious duty of all Muslims in the world," according to the document. The second fatwa was issued by Ayatolla Nouri Hamedani and said "avenging the blood of the martyred leader of the revolution is obligatory for all Muslims," according to the document.

Iranian religious leaders have previously issued fatwas against President Donald Trump and Israeli Prime Minister Benjamin Netanyahu.

The DHS document said the deadly shooting in Austin, Texas, on Sunday "probably preceded the issuance of the fatwas and the motive for the attack has not been confirmed." Authorities are continuing to explore whether there was a terroristic motivation.