Iran fired a salvo of ballistic missiles at Tel Aviv on Tuesday in retaliation to the Israeli campaign against Tehran’s Hezbollah allies in Lebanon and the killing of its chief and that of Hamas. Alarms sounded across Israel and explosions could be heard in Jerusalem and the Jordan River valley after Israelis piled into bomb shelters. Reporters on state television lay flat on the ground during live broadcasts. Reuters journalists saw missiles intercepted in the airspace of neighbouring Jordan. Israeli media reports said as many as 100 missiles had been launched. Iran’s Revolutionary Guards said the missile attack under way was in response to the killing of Hezbollah chief Hassan Nasrallah last week as well as that of Hamas leader Ismail Haniyeh. The Guards threatened to carry out “crushing attacks” against regional Israel if it retaliated after the missile attack. Iran’s Supreme Leader Ayatollah Ali Khamenei gave the order to launch missiles at Israel, a senior Iranian official told Reuters, adding that Tehran “is fully ready for any retaliation” Iran’s mission to the United Nations in New York posted on X that the attack on Israel is a “legal, rational, and legitimate response to the terrorist acts.” “Should the Zionist regime dare to respond or commit further acts of malevolence, a subsequent and crushing response will ensue. Regional states and the Zionists’ supporters are advised to part ways with the regime,” the mission wrote. Air traffic was halted at Israel’s Ben Gurion airport, a spokesman said. “There are currently no takeoffs and landings,” said a spokesman for Israel’s main international airport. Earlier, the military had announced that any ballistic missile strike from Iran was expected to be widespread and told the public to shelter in safe rooms in the event of an attack. The firing of missiles came after Israel said its troops had launched ground raids into Lebanon, though it described the forays as limited. The Israeli campaign in Lebanon is the biggest escalation of regional warfare since fighting erupted in Gaza a year ago. In Washington, US President Joe Biden said the United States was prepared to help Israel defend itself from Iranian missile attacks. “We discussed how the United States is prepared to help Israel defend against these attacks, and protect American personnel in the region,” Biden said on X about a meeting held with Vice President Kamala Harris and the White House national security team earlier in the day. Biden directed the US military to aid Israel’s defence and shoot down missiles targeting Israel, the White House National Security Council (NSC) said. The Iranian missile launches came after Israeli ground troops launched raids into Lebanon and its warplanes bombed from the skies. It marks the biggest escalation of regional warfare since fighting erupted in Gaza a year ago, and follows weeks of intense airstrikes that have decapitated Hezbollah by killing most of its top leaders. More than a thousand Lebanese have been killed and a million have fled their homes. Iran, which sponsors Hezbollah, has vowed to retaliate against Israel, raising fears that war could spill across borders throughout the region, despite efforts by the United States, Israel’s closest and most powerful ally, to contain it. In the latest announced killing of a senior Hezbollah figure, Israel said it had assassinated Muhammad Jaafar Qasir, describing him as a commander in charge of weapons transfers from Iran and its affiliates. The rapid escalation that has engulfed Lebanon into war has killed hundreds.