Dozens of crew members have been rescued after abandoning two oil tankers hit by explosions in the Gulf of Oman.
Ship operators said 21 crew on board the Kokuka Courageous and 23 on the Front Altair had been evacuated.
Iran rescued the 44 after an “accident,” report said, although the cause is unconfirmed. The US Navy said it received two distress calls.
The incident comes a month after four oil tankers were attacked off the UAE.
Oil prices rose as much as 4.5% from a near five-month low following Thursday’s incident.
The cause remains unclear.
The Norwegian-owned Front Altair had been “attacked,” the Norwegian Maritime Authority said, leading to three explosions on board.
A spokesman for Taiwan’s state oil refiner CPC Corp, Wu I-fang, which chartered the Front Altair, said it was carrying 75,000 tonnes of naphtha and was “suspected of being hit by a torpedo”, although this has not been confirmed. Other unverified reports suggested a mine attack.
The ship’s owner, Frontline, said the Marshall Islands-flagged vessel was on fire but denied reports on Iran media it had sunk.
The operator of the Panama-flagged Kokuka Courageous, BSM Ship Management said its crew abandoned ship and were rescued by a passing vessel.
”The tanker was carrying methanol and was not in danger of sinking,” a spokesman said. It is currently located about 80 miles from Fujairah in the UAE and 16 miles from Iran. The cargo remains intact.
Report said Iran had rescued the crew members and they had been taken to the port of Jask.
Iranian Foreign Minister Mohammad Javad Zarif tweeted that the incident happened as Japanese PM Shinzo Abe was meeting Iran’s supreme leader, Ayatollah Ali Khamenei, adding: “Suspicious doesn’t begin to describe what likely transpired this morning.”
The vessels were carrying what Japan trade officials said was “Japan-related cargo”.
The initial reports of the blasts came through the Royal Navy linked UK Maritime Trade Operations UKMTO safety group, which issued a warning, urging “extreme caution” in the area.
The US 5th Fleet, based in Bahrain, said it had sent the USS Bainbridge to assist.
Spokesman Josh Frey said in a statement: “US naval forces in the region received two separate distress calls at 06:12 local time (03:12 GMT) and a second one at 07:00.”
Sensitivity of the incidence
The Gulf of Oman lies at one end of the strategic Strait of Hormuz, and this incident will further increase tension in a vital shipping lane through which hundreds of millions of dollars of oil pass.
The US sent an aircraft carrier strike group and B-52 bombers to the region at the start of May in response to what it said was an unspecified plan by Iran-backed forces to attack US forces in the area.
President Donald Trump has taken a hard line towards Iran, accusing it of being a destabilising force in the Middle East.
Iran rejected the claims and has accused the US of aggressive behaviour.
Those tensions rose markedly after the May 12 limpet mine attacks on four tankers off the UAE.
The UAE blamed an unnamed “state actor.” The US said that actor was Iran, an accusation Tehran has denied.
While it is unclear why Iran would carry out a relatively low-level attack on the multinational tankers, observers have speculated that it could have been to send a signal to forces ranged against it that it is capable of disrupting shipping there without triggering a war.