Dubai. Iran and Iranian-backed militias fired missiles at Israel and Arab states, and Israel and the United States pounded targets in Iran as the war expanded on Monday with statements of defiance and increasing casualties.

As the American and Israeli airstrikes continued, top Iranian security official Ali Larijani vowed defiantly on X that “we will not negotiate with the United States.”

In Iraq, a pro-Iranian militia claimed responsibility for a drone attack targeting US troops at the Baghdad airport, the day after it said it fired at a US base in the city of Irbil in the north, and Cyprus said a drone attack targeted a British base on the Mediterranean island nation.

Israel and the US bombed Iranian missile sites and targeted its navy, claiming to have destroyed its headquarters and multiple warships. More than 200 people have been killed since the start of the strikes, according to Iranian leaders.

As the bombardment continued, Hezbollah said it fired missiles from Lebanon into Israel early Monday in response to the killing of Iranian Supreme Leader Ali Khamenei and “repeated Israeli aggressions.” It was the first attack the Lebanese militant group has claimed in more than a year. There were no reports of injuries or damage, and Israel said that it had intercepted one projectile while several fell in open areas.

Israel retaliated with strikes on Lebanon, killing at least 31 people and wounding 149 others, according to Lebanon's Health Ministry. About two-thirds of the dead were in the country's south.

Following its initial strikes on Beirut, Israel urged civilians in nearly 50 villages in eastern and southern Lebanon to evacuate ahead of more possible attacks, sending people fleeing.

Iran has been firing missiles at Israel and Arab states in a counteroffensive since the joint American-Israeli attack Saturday that killed Khamenei and many top Iranian officials.

Gulf Arab states have warned that they could retaliate against Iran after strikes that hit key sites and killed at least five civilians, and US President Donald Trump promised Washington would “avenge” the deaths of three American troops who were killed in Kuwait.

“Sadly, there will likely be more before it ends,” Trump said. “That’s the way it is.”

Trump has urged Iranians to “take over” their government and, while he has also signaled he would be open to dialogue with new leadership there following the death of Khamenei, suggested Sunday there was no end in sight to the military operations.

“Combat operations continue at this time in full force, and they will continue until all of our objectives are achieved,” he said in a video message. “We have very strong objectives,” he added, without elaborating.

The US military said B-2 stealth bombers struck Iran’s ballistic missile facilities with 2,000-pound bombs. Trump said on social media that nine Iranian warships had been sunk and that the Iranian navy’s headquarters had been “largely destroyed.”

In an indication the conflict could draw in other nations, Britain, France, and Germany said they were ready to work with the US to help stop Iran’s attacks, and a group of Gulf Arab countries said it reserved the right to respond to Iranian strikes.

The weekend attacks were the second combined strikes in eight months from the US and Israel against Iran. In the 12-day war last June, Israeli and American strikes greatly weakened Iran’s air defenses, military leadership and nuclear program. But the killing of Khamenei, who ruled Iran for more than three decades, creates a leadership vacuum, increasing the risk of regional instability.