As Iran retaliates, largest US military base in Middle East hit by ballistic missile, Qatar says

Six U.S. service members have been killed since the operation against Iran began, according to U.S. Central Command.

"U.S. forces recently recovered the remains of two previously unaccounted for service members from a facility that was struck during Iran's initial attacks in the region," CENTCOM said in a statement Monday. "Major combat operations continue."

All six deaths occurred from a single incident in Kuwait, sources told ABC News.

The names of the fallen troops will be withheld until 24 hours after next of kin notification, CENTCOM said.

An Islamic Revolutionary Guard Corps commander said the Strait of Hormuz is "closed."

"The strait is closed, and whoever wants to cross, our heroes in the navy of the IRGC and army will set those ships on fire," Brigadier General Ebrahim Jabari said on Iranian state TV earlier.

The Strait of Hormuz is one world's most important chokepoints for oil. Roughly 20% of the world’s oil passes through the Strait, according to the U.S. Energy Information Administration.

The Israel Defense Forces said the Israeli Air Force has "struck and dismantled" the Iranian state broadcaster "a short while ago."

"The center was also recently used by the Iranian regime's forces to advance military activities under the guise of civilian activity and assets, in addition to the propaganda activities that emanate from the communications center," the IDF said in a statement.

"The IDF will continue to strike the Iranian regime's infrastructure across Tehran," the statement added.

The State Department is urging Americans to leave 14 countries in the Middle East immediately "due to serious safety risks," Assistant Secretary Mora Namdar said on X.