Israel announced strikes on government infrastructure in Tehran on Monday.
President Donald Trump announced "major combat operations" against Iran on Feb. 28, with massive joint U.S.-Israel strikes targeting military and government sites, officials said.
Ayatollah Ali Khamenei was among those killed in Tehran on the first day of strikes, and his son Mojtaba Khamenei was chosen to succeed him. Iran is responding with missile and drone attacks targeting Israel, regional U.S. bases and multiple Gulf nations. Iran is also attempting to block some shipping traffic through the Strait of Hormuz.
Israel is also intensifying its long-running strike campaign against the Iran-backed Hezbollah militia in Lebanon.
The Red Crescent in Jerusalem said it is treating several injuries after shrapnel of an Iranian missile landed in the Old City. Those who are Injured are being transferred to the hospital.
It is unclear if the shrapnel is from direct missile hits or if it is interception debris.
Three Navy ships carrying 2,200 Marines left San Diego earlier this week for a previously scheduled deployment to the Indo-Pacific, but two U.S. officials tell ABC News their ultimate destination is likely the Middle East.
The 11th Marine Expeditionary Unit (MEU) is aboard the USS Boxer, the USS Comstock and the USS Portland -- along with 2,000 sailors.
The 31st MEU is still on its way to the Middle East from Asia after receiving orders from the Pentagon last Friday. Those Marines and ships are likely to arrive in the region sometime next week.
It will take two weeks for the USS Boxer Amphibious Ready Group to get to southeast Asia, then additional time to make its way to the Middle East if it gets final orders to go there.
Included in the MEU: ground forces, a logistical element and aviation units that include fighter jets, MV-22 Ospreys and attack helicopters.
Last week's deployment of the 31st MEU to the Middle East has sparked speculation as to whether they might be used to seize Kharg Island in the Persian Gulf -- crucial to Iran's oil trade -- or carry out raids on the Iranian shoreline around the Strait of Hormuz.
For now, the U.S. Navy Third Fleet says the 11th MEU is conducting routine operations in its area of operations.
"An integral part of U.S. Pacific Fleet, U.S. 3rd Fleet operates naval forces in the Indo-Pacific to conduct routine training that ensures the continued warfighting readiness of Navy and Marine forces operating in the area," the U.S. Navy Third Fleet said in a statement.
President Donald Trump is again blasting America's NATO allies, calling them "COWARDS" and criticizing them for not helping keep the Strait of Hormuz open amid the war in Iran, in a social media post Friday.
"Now that fight is Militarily WON, with very little danger for them, they complain about the high oil prices they are forced to pay, but don't want to help open the Strait of Hormuz, a simple military maneuver that is the single reason for the high oil prices," Trump said in the post.
The president added that it would be easy for European allies to do and "with so little risk."
"COWARDS, and we will REMEMBER!" Trump said.
The post comes after Trump called repeatedly on allies to help reopen the Strait of Hormuz. Many European and other allies have rebuffed Trump's call to action. On Monday, German Chancellor Friedrich Merz's spokesman said that this is "not NATO's war."
While the president publicly requests help, he also repeatedly says that the U.S. doesn't need the help of their allies.
"We're the strongest nation in the world. We have the strongest military by far in the world. We don't need them. But it's interesting," Trump said on Monday.
Kuwait said Friday that its Mina Al-Ahmadi oil refinery was attacked by Iranian drones for the second day.
No injuries were immediately reported, but fires erupted in several of the refinery's units, prompting a partial shutdown, according to the state-owned Kuwait Petroleum Corporation, which operates the facility.
Firefighters were at the scene Friday morning working to extinguish the flames, according to the Kuwait Fire Force.
-ABC News' Morgan Winsor
