Israel has launched a fresh wave of attacks on Iran, which threatened retaliation against vital infrastructure across the Middle East in a war that has plunged the world into its worst energy crisis in decades.
Explosions rang out in Tehran, Iranian media reported, while Saudi Arabia and the United Arab Emirates said they were intercepting missiles and drones.
At least 40 energy assets across the oil- and gas-exporting region have been "severely or very severely damaged" in the conflict, said International Energy Agency chief Fatih Birol, as the war ignited by Israel-US attacks on Iran entered its fourth week.
Iran has met the assaults by firing missiles and drones at Israel and across the Gulf in the last weeks, hitting energy sites and US embassies alike.
It has also throttled traffic in the Strait of Hormuz, a vital waterway through which a fifth of global crude oil transits.
With oil prices hovering above $100 a barrel over supply fears, US President Donald Trump threatened to "obliterate" Iranian power plants if Iran failed to reopen the strait within 48 hours.
The deadline, based on the time of his social media posting, would be 11.44pm Irish time, early morning Tuesday in Iran.
Iran warned it would strike energy and water infrastructure across the Gulf if US President Donald Trump follows through on his threat to attack its electricity grid, raising fears of mass disruption in a region heavily dependent on desalination for drinking water.
The prospect of tit-for-tat strikes on civilian infrastructure further unsettled oil markets, with prices opening choppy in Asia trading.
After more than three weeks of heavy US and Israeli bombardment that officials say has sharply reduced Iran’s missile capabilities, Iran has continued to demonstrate its ability to strike back.
Air raid sirens sounded across parts of northern and central Israel, including in Tel Aviv, and the occupied West Bank overnight, warning of incoming missiles from Iran.
The Israeli military said early this morning it had begun a wide-scale wave of strikes targeting Iranian infrastructure in Tehran.
Iranian news agencies said at least one child was killed and several people were injured in the bombing of a residential area in western Khorramabad city.
A residential neighbourhood in the northwestern city of Urmia was damaged by an air strike, Iranian news agencies reported. Iranian Red Crescent rescuers were shown in a video searching for survivors. There were no immediate reports of casualties.
Mr Trump's warning came less than a day after he signalled the United States might be considering winding down the conflict, even as US Marines and heavy landing craft were heading to the region.
"If Iran’s fuel and energy infrastructure is attacked by the enemy, all energy infrastructure, as well as information technology...and water desalination facilities, belonging to the US and the regime in the region will be targeted pursuant to previous warnings," Iranian military spokesman Ebrahim Zolfaqari said, according to state media.
While attacks on electricity could hurt Iran, they could be catastrophic for its Gulf neighbours, which consume around five times as much power per capita.
Electricity makes their gleaming desert cities habitable, in part by powering the desalination plants that produce 100% of the water consumed in Bahrain and Qatar.
Such plants use seawater to meet more than 80% of drinking water needs in the United Arab Emirates, and 50% of the water supply in Saudi Arabia.
Iran's Parliament Speaker Mohammad Baqer Qalibaf doubled down, writing on X that critical infrastructure and energy facilities in the Middle East could be "irreversibly destroyed" should Iranian power plants be attacked.
Iran's powerful Revolutionary Guards said it would also mean the shipping lane where a fifth of global oil and liquefied natural gas normally transits along Iran's southern coast would remain shut.
"The Strait of Hormuz will be completely closed and will not be opened until our destroyed power plants are rebuilt," the Guards said in a statement.
The Saudi defence ministry said early Monday two ballsitic missiles had been launched towards Riyadh. One missile was intercepted while the other fell in an uninhabited area.
Yesterday, Iranian strikes on two southern Israeli towns injured dozens in what an Israeli hospital described as a major casualty event.
The towns were located close to Israel's secretive nuclear reactor and a number of military installations, including Nevatim Air Base, one of the country's largest.
More than 2,000 people have been killed during the war the US and Israel launched on 28 February, which has upended markets, spiked fuel costs, fuelled global inflation fears and convulsed the postwar Western alliance.
