U.S. Navy explosives experts believe a 'drone strike' targeted an oil tanker that came under attack off the coast of Oman, killing two on board, the U.S. Navy said July 31.

Israel on July 30 blamed Iran for the attack on an Israeli-managed Mercer Street tanker off Oman that killed two crew members -- a Briton and a Romanian.

London-based Zodiac Maritime, part of Israeli billionaire Eyal Ofer's Zodiac Group, said that the Liberian-flagged, Japanese-owned vessel was attacked late on July 29. It did not provide more details about the nature of the attack.

The aircraft carrier USS Ronald Reagan and the guided missile destroyer USS Mitscher were escorting the Mercer Street as it headed to a safe port, the U.S. Navy's Mdidle East-based 5th Fleet said in a statement.

"U.S. Navy explosives experts are aboard to ensure there is no additional danger to the crew, and are prepared to support an investigation into the attack. Initial indications clearly point to a UAV-style attack," the statement said.

"Upon arrival, U.S. forces determined through clear visual evidence that an attack had occurred," the statement added.

Israeli Foreign Minister Yair Lapid blamed Iran, saying he told Britain's foreign secretary of the need for a tough response to the incident.

'Iran is not just an Israeli problem, but an exporter of terrorism, destruction, and instability that harms us all. The world must not be silent in the face of Iranian terrorism that also harms freedom of shipping,' Lapid said in a statement.

Lapid said he has ordered the nation's diplomats to push for UN action against 'Iranian terrorism.'

'I've instructed the embassies in Washington, London and the UN to work with their interlocutors in government and the relevant delegations in the UN headquarters in New York,' Lapid said on Twitter.

There was no immediate official reaction from Iran, which has blamed Israel for being behind the assassination of a top nuclear scientist last year and a series of attacks on nuclear facilities.

Al Alam TV, the Iranian government's Arabic-language television network, cited unidentified sources as saying the attack was in response to a suspected, unspecified Israeli attack on an airport in Syria.

Israel has carried out hundreds of air strikes on Iranian targets in Syria as part of a shadow war between the regional foes. In recent months, vessels linked to each nation have been mysteriously targeted in waters around the Middle East.

Tensions have risen in the Persian Gulf since the United States reimposed sanctions on Iran in 2018 after then-President Donald Trump withdrew the United States from the 2015 nuclear deal with major powers.

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The United States, Israel's closest ally, expressed concern and said it was monitoring the situation.

'We are urgently working with our partners, our international partners, to establish the facts,' a State Department spokeswoman said.

A U.S. official quoted by AP and Reuters said it wasn't immediately known who launched the attack but said it appeared a drone was used.

The United Kingdom Maritime Trade Operations, which provides maritime security information, said the attack was not piracy. It said an investigation was under way.

The statement from Zodiac Maritime said that at the time of the incident the tanker was traveling from Dar es Salaam to Fujairah with no cargo.

Oman's state news agency said the attack took place outside the sultanate's territorial waters.

Zodiac Maritime said the tanker was back under the control of its crew and was heading to an undisclosed 'safe location with a U.S. naval escort.'

With reporting by Reuters, AFP, and AP

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