Amidst increased US presence in the strategic Gulf of Oman, two oil tankers came under attack off the Iran coast on Thursday, in a development that could further deter countries from sourcing crude from Iran and thereby cause a spike in oil prices.
Oil prices zoomed after a merchant shipping information service run by Britain's Royal Navy reported the "incident" in the Gulf of Oman.
"UK and its partners are currently investigating," United Kingdom Marine Trade Operations (UKMTO) said on its website, without giving further details.
Global oil prices gained around four per cent immediately after the reports of the attack. Benchmark Brent oil was trading at $61.74 a barrel, up about three per cent.
The Norwegian Maritime Authority said three explosions were reported on board the Norwegian-owned tanker `Front Altair’ after it was "attacked" along with the Singapore-owned cargo carrier `Kokuka Courageous’.
The crew of two oil tankers were evacuated after the vessels caught fire.
The mystery incident, the second involving shipping in the strategic sea lane, send world oil prices soaring.
Iran said its navy had rescued 44 crew members after the two vessels caught fire in "accidents" off its coast.
The US 5th Fleet, based in the region, also said it had received two "distress signals."
The mystery incident, the second involving shipping in the strategic sea lane in only a few weeks, came amid spiralling tensions between Tehran and Washington, which has pointed the finger at Iran over tanker attacks in May.
United States Navy fighter jets were flying missions from an aircraft carrier in the Arabian Sea on Saturday.
Iranian state media said the first incident occurred on board the Front Altair at 8:50 am (0420 GMT) 25 nautical miles off Bandar-e-Jask in southern Iran.
The Marshall Islands-flagged tanker was carrying a cargo of ethanol from Qatar to Taiwan, official news agency IRNA reported.
"As the ship caught fire, 23 of the crew jumped into the water and were saved by a passing ship and handed over to the Iranian rescue unit," it said.
"An hour after the first accident the second ship caught fire at 9:50 am 28 nautical miles off the port."
The Panama-flagged Kokuka Courageous was headed to Singapore from Saudi Arabia with a cargo of methanol, and 21 of its crew jumped and were rescued, according to IRNA.
Singapore-based BSM Ship Management, which owns the Kokuka Courageous, said it had "launched a full-scale emergency response following a security incident".
"The 21 crew of the vessel abandoned ship after the incident on board which resulted in damage to the ship's hull starboard side," it said.
"One crew man from the Kokuka Courageous was slightly injured in the incident and is receiving first aid."
It said the vessel is about 70 nautical miles from the United Arab Emirates and just 14 from the coast of Iran.
Tehran said it has dispatched a helicopter from the port of Bandar-e-Jask to the ships' location for "further investigation".
The Gulf of Oman lies at the other end of the strategic Strait of Hormuz from the Gulf, part of a vital shipping lane through which at least 15 million barrels of crude oil and hundreds of millions of dollars of non-oil imports pass.
On May 12, four oil tankers -- two Saudi, one Norwegian and one Emirati -- were damaged in still unexplained attacks in the Gulf of Oman off the United Arab Emirates.