The US and Iran have exchanged strikes across the Middle East for a second consecutive day, further straining an already shaky ceasefire agreed between the two countries in April.
US Central Command (Centcom) said it had completed a wave of "self-defense strikes" targeting military, surveillance and radar sites in southern Iran.
The attack came hours after President Donald Trump vowed US forces would hit Iran "hard", and that Tehran had taken "too long to make a deal" to permanently end the war.
In response, Iran launched a round of strikes targeting US military assets in countries across the region.
US military bases in Bahrain and Kuwait came under Iranian fire for a second day in a row, while Iran's Islamic Revolutionary Guard Corps (IRGC) said it fired ballistic missiles at a US command centre in Jordan, according to Iranian state media.
Bahrain's interior ministry said its air raid sirens were activated overnight, as Kuwait's Army posted on X that its anti-air defence systems intercepted "hostile aerial targets".
Kuwait said it had temporarily closed its airspace due to the Iranian attacks.
In the latest flare-up, the IRGC also said it had hit two oil tankers passing through the Strait of Hormuz, Iranian state media reported, although there was no immediate confirmation of the strike.
That came after Iranian state media reported that the Strait of Hormuz was "completely closed to all type of vessel". Centcom, however, said "commercial ships are continuing to transit in and out of the Strait of Hormuz".
Oil prices rose shortly after the closure of the shipping channel and the apparent attack on the ships was announced.
Brent crude oil, seen as the global benchmark, climbed to around $95 a barrel after rising by about 2%.
Hours before the US launched its latest attack, Trump had warned: "We hit them hard yesterday and we're going to hit them hard again today."
Trump wrote on Truth Social that Iranian leaders have "taken too long to negotiate a deal".
US Defence Secretary Pete Hegseth said Iran had been given a chance to make a deal but had not taken it, adding that bombs would be "dropping on key facilities" in the country.
The US president added that Iran would be attacked again if no peace deal was secured.
Iranian President Masoud Pezeshkian said Iran "will stand firm against any pressure or threat". The Iranian foreign ministry earlier accused the US of "damaging the diplomatic process through the contradictory messages it sends".
In April, the US and Iran agreed a ceasefire that was initially meant to last for two weeks. Both sides have since exchanged intermittent fire, without returning to full-scale hostilities.
However, recent efforts to broker negotiations between Washington and Tehran have stalled and attacks have ramped up.
This week, a US helicopter was downed in an attack that was blamed on Iran. The IRGC responded by targeting US bases across the Middle East.
In a statement on X, UN Secretary General António Guterres said the Middle East was "being pulled deeper into crisis", and recent attacks meant "the ceasefire is more like a lesser-fire".
"We should not minimize the risks of lesser fire becoming full fire. All parties must work towards a diplomatic settlement. No more attacks. No more excuses," he said in a statement.
