A day after Israel killed Iran's powerful security chief Ali Larijani in the highest-level assassination since the war's first day, Iran retaliated by firing missiles with multiple warheads into Israel that Israeli authorities said killed two people near Tel Aviv.
Iran said the killing of Larijani and other officials would not hinder its operations. Foreign Minister Abbas Araqchi said the United States and Israel failed to understand that the Islamic Republic was a robust political system that did not depend on any single individual.
Nearly three weeks into the conflict, there are scant signs of de-escalation.
An unprecedented disruption to global energy supplies has raised the political stakes for US President Donald Trump. Diesel prices in the United States rose above $US1 a litre on Wednesday for the first time since the 2022 inflation surge that eroded support for his predecessor Joe Biden.
Israel has stepped up its strikes on Lebanon and a ground assault in the south in pursuit of the Iran-backed Hezbollah group, which has fired across the border in solidarity with Tehran.
Iran's new supreme leader, Mojtaba Khamenei, has rejected proposals conveyed to Tehran by intermediary countries to de-escalate the conflict, saying that the United States and Israel must first be "brought to their knees", according to a senior Iranian official who asked not to be identified.
In central Beirut's Bachoura district, Israel warned residents to leave a building, which it then completely flattened. Eyewitness video, verified by Reuters, showed the structure crumbling into dust as it was struck at dawn. Firefighters later clambered over a vast pile of smoking rubble.
No such warning was given for strikes that hit apartment buildings in two other central districts, according to Lebanese authorities. Smoke poured from the balcony of one building as residents swept debris from the street, surrounded by wrecked cars.
While Israel has been striking Hezbollah-controlled southern suburbs of Beirut for days, the latest attacks were among the worst to hit central parts of the capital in decades.
Inside Israel, an Iranian missile tore a crater into the pavement and set cars ablaze in a residential area of Holon, just south of Tel Aviv.
"There was an alarm, we went into the shelter, we heard a crazy boom," resident Leah Palteal told Reuters. "When we were allowed to come out... We saw fire, we went downstairs, we saw that everything here was blown up."
Israel has also launched a ground assault in southern Lebanon. It acknowledged on Wednesday that its troops had fired from a tank at a UN base a week into the war, injuring three Ghanaian peacekeepers in what it said was a mistake.
Lebanese authorities say 900 people have been killed in the country and 800,000 forced to flee their homes.
US-based Iran human rights group HRANA said on Monday that an estimated 3000-plus people have been killed in Iran since the US-Israeli attacks began at the end of February.
Iran said it had executed a man convicted of spying for Israel, media outlet Mizan reported on Wednesday.
The man, identified as Kurosh Keyvani, had been convicted of providing Israel's spy agency Mossad with pictures and information about sensitive locations in Iran, it said.
Iranian attacks have killed people in Iraq and across the Gulf states. Fourteen have been killed in Israel.
Israel and the United States say their war aim is to prevent Iran from being able to project force beyond its borders and destroy its nuclear and missile programs.
They have also urged Iranians to rise up and overthrow their clerical rulers, just weeks after authorities killed thousands of anti-government protesters. However, there has been no sign of organised dissent inside Iran since the bombing began.
The Israel Defence Forces said it struck targets in Tehran on Tuesday that included the headquarters of the Revolutionary Guards' security unit tasked with suppressing unrest, and a maintenance centre linked to Iran's internal security forces.
Iran told the UN nuclear watchdog that a projectile had also hit an area near the Bushehr nuclear power plant on Tuesday evening but caused no damage or injuries. IAEA chief Rafael Grossi reiterated his call for maximum restraint.
The United States military said on Tuesday it had targeted sites along Iran's coastline near the Strait of Hormuz with powerful "bunker-buster" bombs, saying Iranian anti-ship missiles there posed a threat to international shipping.
The strait, where a fifth of global oil and liquefied natural gas supplies normally pass within a few miles of Iran's coast, remains largely closed as Iran threatens to attack tankers linked to the US and Israel. Oil prices have surged.
Saudi Arabia will host a consultative meeting of foreign ministers from a number of Arab and Islamic countries in Riyadh later on Wednesday to discuss ways to support regional security and stability.
with AP and DPA
