Tanker Sunk in Strait of Hormuz? What Iran’s Guards Claim

Iran’s Islamic Revolutionary Guard Corps has claimed that a supertanker carrying more than two million barrels of crude oil sank in what it called the southern waters of the Persian Gulf on November 15, after it and a second tanker struck naval mines on an unauthorised route in the southern part of the Strait of Hormuz. The Guards’ statement, broadcast on Sunday afternoon, said both strikes had taken place over the previous few hours and that the second tanker had been left burning. It named neither vessel, gave no flag, owner or position, and came without any imagery of a sinking. The claim marks a significant escalation in the Guards’ wording, going beyond the fires and halted ships Tehran has described almost daily since late October to assert the loss of a fully laden crude carrier.

What maritime authorities have actually put on record about Sunday’s incidents is considerably narrower. The UK Maritime Trade Operations centre stated on November 15 that it was aware of a report, received from Indian shipping authorities, of an attack on a tanker sailing eastbound through the Gulf before it entered the strait, with all crew accounted for and safe and the extent of damage and any environmental impact unknown. The centre urged vessels to transit with caution and said it was unclear whether this was the incident the Guards had announced. No shipowner, flag state or naval force had confirmed a sinking by Sunday evening, a pattern familiar from the running tally of mine claims, in which Iran’s forces said at least 12 tankers struck mines between October 31 and November 5 without a single vessel being named.

A sinking of the kind the Guards describe would be far from routine in these waters. Two million barrels is roughly the full load of a Very Large Crude Carrier, and losing such a cargo would rival the 1979 loss of the Atlantic Empress in the Caribbean, which released some 287,000 tonnes of oil and remains the largest tanker spill on record. Large tankers have also proven notably hard to sink with a single mine, with the reflagged Kuwaiti supertanker Bridgeton having struck a mine during its first U.S. Navy escorted convoy in July 1987 and completed its voyage under its own power. Of the merchant ships known to have sunk since the war began on February 28, the container ships Safeen Prestige and GFS Pride and the bulk carrier Cape Dao all sank after projectile strikes, while the only tanker confirmed sunk, the Iranian Kylo, was destroyed by U.S. forces on September 5 by Central Command’s account.

The Guards’ navy declared the strait unsafe and closed on November 5 to any vessel that does not coordinate its passage with Tehran, and has since described the ships it says were hit as sailing with their tracking systems switched off, often, it alleges, with covert U.S. military support, while the U.S. military states that it has cleared mines from the main shipping routes. The tanker announcement came on the same day the Guards said they had sent six drones against a U.S. air defence radar at Riffa in Bahrain, where the Bahrain Defence Force said its air defences had destroyed several Iranian aerial attacks before they reached their targets. Before the war began, the strait carried roughly one fifth of the oil consumed worldwide.