The escalation heightened fears that the spiraling war in the Middle East -- which began with a massive U.S.-Israeli assault on Iran on Saturday -- could continue to draw in more countries across the region.
Hezbollah first launched rockets at Israeli territory overnight in what it said was retaliation for the death of Ayatollah Ali Khamenei, Iran's supreme leader, who was killed in a joint U.S.-Israeli military operation on Saturday. Israel said it had responded by attacking sites south of Beirut affiliated with Hezbollah; Lebanese state media reported that at least 31 people had been killed.
The conflict has now entered its third day with little end in sight. The United States and Israel have conducted thousands of airstrikes across Iran, including the capital of Tehran, while Iran fired drones and missiles at Israel and U.S. allies in the Persian Gulf.
On Sunday, the U.S. military announced that three American soldiers had been killed in a base in Kuwait, while another nine people were killed in a strike in central Israel. Iranian state media reported that at least 115 people, many of them children, had been killed at a girls' elementary school near a naval base in southern Iran. At least 31 people were killed in Lebanon in Israeli airstrikes, the authorities said early Monday, according to state media.
President Trump has framed the war as an effort to decimate much of Iran's military capabilities and to pave the way for the ouster of the decades-long authoritarian rule of the Islamic Republic. In an interview with The New York Times, Mr. Trump said the United States intended to keep up the attack on Iran for "four or five weeks." Critics say the Trump administration has no clear endgame and that the casualties are already beginning to mount.
Mr. Trump said that Iran's new leaders had communicated that they wanted to engage with him and that he was willing to do so. But early Monday, Ali Larijani, Iran's top national security official, said on social media that the Islamic Republic would not negotiate with the United States, adding that Mr. Trump's "wishful thinking" has dragged the region into an unnecessary war that only benefited Israel.
The Israeli military said on Sunday that it had struck Iranian missile launchers, air defense systems, plus government headquarters and command centers. U.S. forces struck Iran's "hardened" ballistic missile facilities, destroyed the headquarters of the Islamic Revolutionary Guards Corps and sank at least one warship, the military said.
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