Video released by the US military allegedly shows Iran’s Revolutionary Guard removing an unexploded mine from the side of an oil tanker after it was attacked in the Gulf of Oman.
Black-and-white footage recorded by a US aircraft shows a smaller boat, said to be an IRGC patrol boat, approaching the Japanese-owned oil tanker, while photos show the apparent magnetic mine attached to the ship before it was removed.
Washington has blamed Tehran for attacks on two oil tankers – the Kokura Courageous and Norwegian-owned Front Altair – which rattled global oil markets amid escalating tensions between the two nations.
Iran has denied responsibility, saying on Friday that America’s accusations were “alarming” and it rescued the crew of the attacked tankers “in the shortest possible time”.
The crew of both vessels were forced to abandon ship as both tankers suffered explosions in a crucial shipping lane in waters between Iran and Gulf Arab states.
Navy Captain Bill Urban, a spokesman for the US military’s Central Command, claimed a Revolutionary Guard (IRGC) boat approached the Kokura Courageous at 4.10pm local time on Thursday.
The video was recorded about ten hours after the first distress call.
He said: “(It) was observed and recorded removing the unexploded limpet mine from the Kokura Courageous.”
The US said its Navy forces received distress calls from the Altair at 6.12am and the Kokura Courageous at 7am after they were attacked.
Mr Urban said US aircraft observed an IRGC Hendijan-class patrol boat and multiple IRGC fast attack craft and fast inshore attack craft near the Altair about an hour after the Kokura Courageous’ distress call.
At 9.26am, he said, Iranian forces told a ship that had rescued sailors from the Altair “to turn the crew over to the Iranian (fast inshore attack craft)”.
Mr Urban added: “The motor vessel Hyundai Dubai complied with the request and transferred the crew of the Altair to the Iranian (vessels).”
Iran has denied that it was responsible for the attacks, accusing the US of “warmongering”.
Foreign Ministry spokesman Abbas Mousavi told state radio: “We are in charge of maintaining security of the Strait and we rescued the crew of those attacked tankers in the shortest possible time.
“US Secretary of State (Mike) Pompeo’s accusations towards Iran is alarming.”
Mr Urban, of the US military, said earlier: “The United States has no interest in engaging in a new conflict in the Middle East.
“However, we will defend our interests.”
The attacks escalated fears over a US-Iran confrontation, and drove up crude oil prices by more than four per cent in the aftermath.
Britain, meanwhile, is backing US claims that Iran was responsible for the attacks.
Mr Pompeo said Washington’s conclusion was responsible based on intelligence and the expertise needed to carry out the operation.
Foreign Secretary Jeremy Hunt said if it is proven that Tehran was behind the incident it would be a “deeply unwise escalation which poses a real danger to the prospects of peace and stability in the region”.
Mr Hunt told the BBC: “This is deeply worrying and comes at a time of already huge tension. I have been in contact with (Mr) Pompeo and, while we will be making our own assessment soberly and carefully, our starting point is obviously to believe US allies.
“We are taking this extremely seriously and my message to Iran is that if they have been involved, it is a deeply unwise escalation which poses a real danger to the prospects of peace and stability in the region.”
Downing Street earlier called the suspected attacks “completely unacceptable”.
An alert urging “extreme caution” was issued by the Navy-run United Kingdom Maritime Trade Operations following reports of explosions.
The blasts, close to the entrance of the Strait of Hormuz, came a month after four vessels were targeted in alleged sabotage attacks off the coast of the United Arab Emirates.
Almost a fifth of the world’s oil – about 17.2 million barrels per day – passes through the Strait.
Tensions between Washington and Tehran have escalated after US President Donald Trump pulled out of a 2015 nuclear deal between Iran and world powers.
In May, Mr Trump also acted to force Iran’s oil customers to slash their imports to zero or face financial sanctions.
The nuclear deal – reached while ex-president Barack Obama was in the White House – aimed to curb Iran’s Tehran’s nuclear ambitions in exchange for sanctions relief.
Iran has warned that it would block the Strait of Hormuz if US sanctions prevent it from selling its oil.
Its oil exports dropped to roughly 400,000 barrels per day in May from 2.5million in April last year.