The clashes mark one of the biggest exchanges in hostilities since the two countries agreed to a ceasefire in April.
The Iranian strikes, which included attacks in Kuwait and Bahrain, came after the US military said on X it had targeted Iranian air defence, ground control stations and surveillance radar sites near the strait in response to what US President Donald Trump said was the downing of a US Apache helicopter on Tuesday.
"I believe the response should be very strong, very powerful, and that's what this one is," Trump told ABC News on Tuesday.
The escalation in violence deepens doubts about the prospects for a deal to end the war that started on February 28 with joint US-Israeli strikes against Iran.
Tehran responded by firing on Gulf neighbours that host US bases and all but choked off the Strait of Hormuz, a vital conduit for oil and gas.
The latest US strikes lasted around four hours before the US Central Command posted just before 9pm on Tuesday (11am Wednesday AEST) that they had ended.
A US official said almost 20 Iranian targets had been struck.
Iran's state media reported that Qeshm island and the port city of Sirik in the Strait of Hormuz were attacked.
Sounds of explosions were heard in nearby Bandar Abbas, and later in the vicinity of Jask, near the entrance to the strait, Iranian media reported, citing local sources and residents.
Iran's Revolutionary Guards said in response they had targeted four sites at the US al-Azraq base in Jordan using long-range missiles, Iranian media reported.
Targets included F-35 fighter jet hangars and a command-and-control centre, and warned they were ready to deliver a "crushing and decisive" response to any further US attack.
Jordanian armed forces said they had intercepted and shot down five missiles launched from Iran toward al-Azraq.
The Kuwaiti army said its air defence systems were engaging hostile aerial targets after Iran's Revolutionary Guards said they had targeted the Ali Al Salem base in Kuwait with drones.
Iran's Revolutionary Guards said earlier they attacked the US Fifth Fleet in Bahrain with drones and threatened "more severe responses" if hostilities continued.
Bahrain's Interior Ministry said a warning siren had been sounded and urged the public to head to safety. Air defences had repelled Iranian attacks, a media adviser to Bahrain's king said.
A US official, speaking on condition of anonymity, said initial assessments showed nearly all missiles and drones launched by Iran were intercepted and they were not immediately aware of any reports of harm to US personnel or damage to US locations.
On Tuesday, a US Apache helicopter was brought down by an Iranian attack drone, according to a US official who spoke on condition of anonymity. Two US pilots involved in the helicopter incident were uninjured, Trump said.
Iran's state media cited a military source as saying that no offensive air military operations had been conducted in the Strait of Hormuz in the previous 24 hours.
A US Navy surface drone found and rescued the two crew, the US military said, after the US Army attack helicopter went down in waters near Oman's coast while on patrol at around 3am on Tuesday.
The US military's Central Command said the two crew were rescued after two hours and were in stable condition.
Iran's Foreign Minister Abbas Araghchi said on X Iranian forces "will leave no attack or threat unanswered".
"Leave our region if you want to be safe."
— Seyed Abbas Araghchi (@araghchi) June 9, 2026Despite its defeats on the battlefield, the U.S. opted to test our determination.Our Powerful Armed Forces will leave no attack or threat unanswered.Leave our region if you want to be safe.History of the Persian Gulf has many chapters on dire fates of intruding outsiders. pic.twitter.com/O17GGtklxA"To reduce risk, best solution is for them to leave," he wrote.
Trump told The Wall Street Journal the helicopter incident "wasn't a big deal" and stressed that "the pilot is fine".
However, the episode could well add further strain to efforts to broker a peace deal to end the wider Middle East war and reopen Hormuz.
Trump has repeatedly said Iran and the US are close to an agreement, though there have been few signs of progress since a tenuous ceasefire took effect in early April.
with dpa
