Updated May 4, 2026 at 1:52 PM EDT
DUBAI, United Arab Emirates — The U.S. military said it battled Iranian forces and sank six small boats as it moved to reopen the Strait of Hormuz on Monday. The United Arab Emirates, a key American ally, said it had come under attack from Iran for the first time since a fragile ceasefire took hold in early April.
The attacks appeared to be in response to U.S. President Donald Trump's latest efforts to reopen the strait, a critical waterway for global energy. The U.S. military said two American-flagged merchant ships had successfully transited the strait on Monday as part of a new initiative.
The UAE Defense Ministry said Iran had launched four cruise missiles, with three shot down and one falling into the sea. Authorities in the eastern emirate of Fujairah said an Iranian drone sparked a fire at a key oil facility, wounding three Indian nationals. The British military reported two cargo vessels ablaze off the UAE.
Breaking Iran's chokehold on the strait would ease global economic concerns and deny Tehran a major source of leverage. But such efforts also risk reigniting the full-scale fighting that erupted when the U.S. and Israel first attacked Iran on Feb. 28, prompting it to close the strait.
Reports of new attacks raised doubts as to whether shipping companies, and their insurers, would take such a risk given that Iran has fired on ships in the waterway and vowed to keep doing so. Iran has said the new U.S. effort is a violation of the fragile ceasefire that has held for more than three weeks.
U.S. says it has reopened a lane through the strait
Iran's effective closure of the strait, which runs between Iran and Oman, has caused a spike in worldwide fuel prices and rattled the global economy. The U.S.-led Joint Maritime Information Center had advised ships Monday to cross the strait in Oman's waters, saying it had set up an "enhanced security area."
Adm. Brad Cooper, commander of U.S. Central Command, told reporters that American forces have successfully opened a passage through the strait that is free of Iranian mines. He said Iran launched multiple cruise missiles, drones and small boats at civilian ships under the U.S. military's protection.
U.S. military helicopters sank six of the small boats, Cooper said, adding that "each and every" threat had been defeated.
"The U.S. commanders who are on the scene have all the authority necessary to defend their unit and to defend commercial shipping -- as we saw and demonstrated earlier today," Cooper said.
Trump had warned Sunday that Iranian efforts to halt passage through the strait "will, unfortunately, have to be dealt with forcefully."
He described "Project Freedom" in humanitarian terms, designed to aid stranded seafarers on hundreds of ships that have been stuck in the Persian Gulf since the war began.
Iran's state-run IRNA news agency called the effort part of Trump's "delirium."
Missile alerts in the UAE for the first time since ceasefire began
The UAE condemned what it called "renewed treacherous Iranian aggression" and called for an immediate halt to the attacks.
Four missile alerts were issued Monday urging UAE residents to find shelter — the first such alerts since the ceasefire began nearly a month ago. Commercial planes bound for the UAE, home to the global travel hubs of Dubai and Abu Dhabi — turned around midair.
The extent of the attack on Fujairah was unclear, but it is the terminus of a pipeline the UAE has used to avoid shipping some of its oil through the strait. The emirate on the Gulf of Oman is home to extensive oil storage facilities and is the UAE's main sea access outside the strait.
"These attacks represent a dangerous escalation and an unacceptable violation," the UAE's Foreign Ministry said in a statement on X.
Iran stands firm on its grip of the strait
Iran's military command has warned that ships passing through the strait must coordinate with them.
"We warn that any foreign military force — especially the aggressive U.S. military — that intends to approach or enter the Strait of Hormuz will be targeted," Maj. Gen. Ali Abdollahi told state broadcaster IRIB.
The South Korean government said an explosion and fire had broken out aboard a South Korean-operated ship anchored in the strait off the UAE. No injuries were reported. It was not immediately known if the vessel was one of the burning ships reported by the British military's United Kingdom Maritime Trade Operations center.
Trump said in a social media post that Iran had "taken some shot" at a South Korean cargo ship, without elaborating.
The UAE accused Iran of targeting a tanker linked to its main oil company with two drones as it navigated the strait. It did not say when the attack occurred. No injuries were reported.
The disruption of the waterway has squeezed countries in Europe and Asia that depend on Persian Gulf oil and gas, raising prices far beyond the region.
The U.S. has warned shipping companies they could face sanctions for paying Iran for transit of the strait.
The U.S. has meanwhile enforced a naval blockade on Iranian ports since April 13, telling at least 49 commercial ships to turn back, according to Central Command.
The blockade has deprived Tehran of oil revenue it needs to shore up its ailing economy. U.S. officials have expressed hope that the blockade will force Iran to make concessions in talks on its disputed nuclear program and other longstanding issues.
Little progress seen in negotiations
Iran's latest proposal for ending the war calls for the U.S. lifting sanctions, ending the blockade, withdrawing forces from the region and ceasing all hostilities, including Israel's operations in Lebanon, according to the semiofficial Nour News and Tasnim agencies, which have close ties to Iran's security apparatus.
Iranian officials said they were reviewing the U.S. response, though Foreign Ministry spokesperson Esmail Baghaei told reporters Monday that changing demands made diplomacy difficult. He did not give details.
Iran has claimed its proposal does not include issues related to its nuclear program and enriched uranium — long a driving force in tensions with the U.S. and Israel.
Iran wants other issues resolved within 30 days and aims to end the war rather than extend the ceasefire. Trump expressed doubt over the weekend that the proposal would lead to a deal.
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