DUBAI, United Arab Emirates (AP) — U.S. forces fired on and disabled two Iranian oil tankers on Friday after exchanging fire with Iranian forces in the Strait of Hormuz overnight. The United Arab Emirates, meanwhile, reported another Iranian missile and drone attack.

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The attacks cast more doubt on a tenuous month-old ceasefire that the United States has insisted is still in effect. Washington is awaiting an Iranian response to its latest proposal for a deal to end the war, reopen the strait and roll back Tehran's disputed nuclear program.

U.S. Secretary of State Marco Rubio said he hopes to receive "a serious offer" from Iran later Friday.

The U.S. military said Friday that its forces had disabled two Iranian tankers that were trying to breach an American blockade of Iran's ports. Hours earlier, the military said it thwarted attacks on three Navy ships and struck Iranian military facilities in the strait.

Iran has mostly blocked the critical waterway for global energy since the U.S. and Israel launched the war on Feb. 28, causing a global spike in fuel prices and rattling world markets. The U.S. has imposed its own blockade of Iran's ports.

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The UAE's Defense Ministry meanwhile said three people were wounded after air defenses engaged two ballistic missiles and three drones launched by Iran. It was not clear if all were successfully intercepted.

U.S. says it responded to an attack in the strait

The U.S. military posted video of the two Iranian tankers as their smokestacks were struck by an American fighter jet on Friday. Earlier in the week, an American military jet shot out the rudder of a tanker the U.S. military said was attempting to breach its blockade.

Late Thursday, the U.S. military said it thwarted Iranian attacks on three Navy ships in the Strait of Hormuz and struck Iranian military facilities in response. It said no American ships were hit.

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"They threaten Americans, they are going to be blown up," Rubio told reporters Friday.

Iran's Foreign Ministry condemned what it called "hostile" U.S. military action, saying it violated the ceasefire. "Every time a diplomatic solution is on the table, the U.S. opts for a reckless military adventure," Iranian Foreign Minister Abbas Araghchi posted on X.

A U.S. strike overnight killed at least one sailor and injured 10 others aboard a cargo vessel that caught fire, a news agency affiliated with Iran's judiciary reported. It was not clear if the ship was one of the two tankers the U.S. acknowledged striking.

U.S. President Donald Trump has insisted the ceasefire is holding. He also has reiterated threats to resume full-scale bombing if Iran doesn't accept an agreement to reopen the strait and roll back its nuclear program.

Pakistani Prime Minister Shehbaz Sharif said his country has been in contact with the U.S. and Iran "day and night" in an effort to extend the ceasefire and reach a peace deal.

Images show apparent oil slick off Iranian terminal

Satellite images reviewed by The Associated Press show what appears to be an oil slick in the Persian Gulf emanating from the western side of Kharg Island, Iran's main crude export terminal.

Images taken Friday show the slick covering about 71 square kilometers (27 square miles) and appear to show oil still leaking from the terminal, said Ami Daniel, CEO of maritime intelligence firm Windward AI.

Daniel estimated the equivalent of roughly 80,000 oil barrels has spilled from Kharg Island since the slick was first detected by satellite images Tuesday. It's unknown whether the spill was caused by a malfunction, an airstrike or something else.

"This is the risk of fighting in an oil-rich area," said Daniel, adding that it's unlikely any cleanup efforts will be launched in Gulf waters that have become an active war zone.

He said the spill appears to be spreading southwest and within the next two weeks could potentially reach the shores of the UAE, Qatar or Saudi Arabia.

Nina Noelle, an international crisis operations expert with Greenpeace Germany, said Friday recent images show the spill beginning to disperse and it appears unlikely that it will impact land, though it could still possibly affect some sensitive marine habitats.

"More likely, it will dissipate offshore under prevailing conditions," Noelle said.

The Pentagon declined to comment on whether the U.S. military was tracking the spill or whether there had been recent strikes on the Iranian island. Based on the imagery taken earlier this week, the spill occurred before the most recent round of U.S. strikes.

Rubio says `unacceptable' for an Iranian agency to control strait

Rubio said Friday that it's "unacceptable" for Iran to have a government agency that vets and taxes ships seeking passage through the strait.

Lloyd's List Intelligence, a shipping data company, reported Thursday that Iran has created such an agency, known as the Persian Gulf Strait Authority.

The Iranian effort to formalize control over the channel raised new concerns about international shipping, with hundreds of commercial vessels bottled up in the Persian Gulf and unable to reach the open sea.

"Is the world going to accept that Iran now controls an international waterway?" Rubio said. "What is the world prepared to do about it?"

Iran has effectively closed the strait, a vital waterway for the shipment of oil, gas, fertilizer and other petroleum products, while the U.S. is blockading Iranian ports.

A Chinese-crewed oil tanker was attacked near the strait. China has continued to import oil from Iran despite the effective closure of the waterway.

China's Foreign Ministry expressed concern, saying the tanker was registered in the Marshall Islands with Chinese crew on board. There were no casualties reported.

An oil tanker that passed through the Strait of Hormuz in mid-April arrived off South Korea's coast on Friday with 1 million barrels of crude. South Korea, which last year imported more than 60% of its crude through the strait, has capped prices of gasoline and other petroleum products.

Finley and Biesecker reported from Washington. Associated Press writers Russ Bynum in Savannah, Georgia; Giada Zampano and Nicole Winfield in Rome, Seung Min Kim in Washington, Sarah El Deeb in Beirut, and Simina Mistreanu in Bangkok contributed.