The United States said Sunday it destroyed the headquarters of Iran’s Revolutionary Guard but reported its first military casualties in the escalating conflict.

US Central Command shared video on X showing missiles launched from a Navy ship hitting an urban compound. “America has the most powerful military on earth, and the IRGC no longer has a headquarters,” CENTCOM said.

President Donald Trump told the Daily Mail the war could last a month, saying “it's always been a four week process.” The Pentagon confirmed three US service members killed, five seriously wounded, and others with minor injuries. “Major combat operations continue and our response effort is ongoing,” it said.

Iran retaliated with missile and drone strikes across the Gulf, hitting Saudi Arabia, UAE, Qatar, Bahrain, Oman, and Israel. Explosions in Beit Shemesh, Israel, killed at least nine people. Ali Larijani, head of Iran’s Supreme National Security Council, vowed: “Today we will hit them with a force that they have never experienced before.”

Iranian President Masoud Pezeshkian called Khamenei’s killing a “declaration of war against Muslims,” adding, “Iran considers it its legitimate duty and right to avenge the perpetrators and masterminds of this historic crime.”

Israel said the operation “eliminated 40 senior commanders, including Khamenei, in one minute,” while Prime Minister Benjamin Netanyahu warned attacks “will only escalate in the days ahead.” Israel mobilized 100,000 reservists.

Gulf states were hit, including Oman’s Duqm port and ships in the Strait of Hormuz. Iran claimed strikes on the USS Abraham Lincoln, which the Pentagon said missed. Trump said US strikes sunk nine Iranian naval vessels and partially destroyed its navy headquarters.

In Tehran, the Red Crescent reported 201 dead and hundreds wounded. Iran named Ayatollah Alireza Arafi to join an interim leadership council as a permanent successor to Khamenei is chosen. Amid the crisis, some Iranians celebrated his death, while others feared for the country’s future.